bluuebunny/crossref_metadata_2025_split huggingface dataset:
Risk factors for alcohol use among male adolescents and emerging adults in Haiti
Authors: Gage Anastasia J. , Suzuki Chiho 
Published: July 2005

ABSTRACTThis study examined risk factors associated with alcohol use in the past 3 months among young men aged 15–24 in Haiti using data from the 2000 Enquête Mortalité, Morbidité et Utilization des Services. Findings indicate that life‐time smoking, multiple sexual partnerships, witnessing inter‐parental conflict in childhood, disruption of parental monitoring, and residing in communities with high levels of youth drinking differentiated experimenters from abstainers. Youth out‐of‐school employment and co‐residence with adults who had a history of drunkenness were among risk factors associated with regular alcohol use. The greater was the number of risk factors to which a young man was exposed, the higher were the probabilities of alcohol experimentation and regular use. The findings call for prevention strategies at the family and community levels and for initiatives that focus on sexual and non‐sexual individual behaviour change.
Does futures exhibit maturity effect? New evidence from an extensive set of US and foreign futures contracts
Authors: Daal Elton , Farhat Joseph , Wei Peihwang P. 
Published: July 2005

AbstractIn a seminal article, Samuelson (1965) [Samuelson, P. A. (1965), “Proof that properly anticipated prices fluctuate randomly,” Industrial Management Review 6, 41–49.] proposes the maturity effect that the volatility of futures prices should increase as futures contract approaches maturity. This study provides new evidence on the maturity effect by examining a more extensive set of futures contracts than previous studies and analyzing each contract separately. Using 6805 futures contracts drawn from 61 commodities, including some data from non‐US markets, we find that the maturity effect is absent in the majority of contracts. In addition, the maturity effect tends to be stronger in agricultural and energy commodities than in financial futures. We also examine the hypothesis in Bessembinder et al. (1996) [Bessembinder, H., J. F. Coughenour, P. J. Seguin, & M. M. Smoller (1996), “Is there a term structure of futures volatilities? Reevaluating the Samuelson hypothesis,” Journal of Derivatives 4, 45–58.], which states that negative covariance between the spot price and net carry cost causes the maturity effect in futures. Our results provide very weak evidence in favor of this hypothesis.
Integration of metabolic networks and gene expression in virtual reality
Authors: Yang Yuting , Engin Levent , Wurtele Eve Syrkin , Cruz-Neira Carolina , Dickerson Julie A. 
Published: July 2005

AbstractMotivation: Metabolic networks combine metabolism and regulation. These complex networks are difficult to understand and visualize due to the amount and diverse types of information that need to be represented. For example, pathway information gives indications of interactions. Experimental data, such as transcriptomics, proteomics and metabolomics data, give snapshots of the system state. Stereoscopic virtual environments provide a true three-dimensional representation of metabolic networks, which can be intuitively manipulated, and may help to manage the data complexity.Results: MetNet3D, a 3D virtual reality system, allows a user to explore gene expression and metabolic pathway data simultaneously. Normalized gene expression data are processed in R and visualized as a 3D plot. Users can find a particular gene of interest or a cluster of genes that behave similarly and see how these genes function in metabolic networks from MetNetDB, a database of Arabidopsis metabolic networks, using animated network graphs. Interactive virtual reality, with its enhanced ability to display more information, makes such integration more effective by abstracting key relationships.Availability: MetNet3D and some sample datasets are available at http://www.vrac.iastate.edu/research/sites/metnet/Download/Download.htmContact: julied@iastate.eduSupplementary information: Color snapshots and movies are available at http://www.vrac.iastate.edu/research/sites/metnet/Bioinformatics/SupplementaryInformation.htm
simuPOP: a forward-time population genetics simulation environment
Authors: Peng Bo , Kimmel Marek 
Published: July 2005

Abstract
Summary: simuPOP is a forward-time population genetics simulation environment. The core of simuPOP is a scripting language (Python) that provides a large number of objects and functions to manipulate populations, and a mechanism to evolve populations forward in time. Using this R/Splus-like environment, users can create, manipulate and evolve populations interactively, or write a script and run it as a batch file. Owing to its flexible and extensible design, simuPOP can simulate large and complex evolutionary processes with ease. At a more user-friendly level, simuPOP provides an increasing number of built-in scripts that perform simulations ranging from implementation of basic population genetics models to generating datasets under complex evolutionary scenarios.
Availability: simuPOP is freely available at http://simupop.sourceforge.net, distributed under GPL license.
Contact: bpeng@rice.edu
Genetic structure of Euphrasia stricta on the Baltic island of Gotland, Sweden
Authors: Kolseth Anna‐Karin , Lönn Mikael 
Published: July 2005

Genetic differentiation between and within five varieties of Euphrasia stricta (var. brevipila, var. gotlandica, var. stricta, var. suecica and var. tenuis) on Gotland was investigated, using amplified fragment length polymorphism, AFLP. The varieties are described in the literature by morphology and association to habitat type. We wanted to investigate whether the varieties are locally adapted populations to the typical habitat type for each variety or if they are preadapted to certain habitat types and have colonized Gotland in their present form.A constrained principal coordinate analysis revealed three genetically differentiated subunits within the species. The two early‐flowering varieties suecica and tenuis each formed a distinct group, while the three late‐flowering varieties brevipila, gotlandica and stricta together formed the third group. A phylogenetic tree confirms the partitioning into three groups. Within the group containing the late‐flowering varieties there are populations that pair as each other's closest relatives, but belong to different varieties. These pairs are also geographically adjacent.The phylogenetic tree had a “star‐like” appearance indicating a stronger divergence between populations than between varieties. The same pattern was seen in the partitioning of genetic diversity, with a lower amount of genetic variation occurring between varieties, FST=0.14, than between populations within the varieties, FST ranging from 0.26 to 0.60.In Euphrasia stricta the varieties suecica and tenuis and the group containing the varieties stricta/gotlandica/brevipila are likely to have a phylogeographical history outside Gotland, or an ancient and concealed local origin on the island. Within the group stricta/gotlandica/brevipila local evolutionary events seem to determine the variety identity, probably through local adaptation.
Relative importance of resource quantity, isolation and habitat quality for landscape distribution of a monophagous butterfly
Authors: Krauss Jochen , Steffan‐Dewenter Ingolf , Müller Christine B. , Tscharntke Teja 
Published: July 2005

Fragmentation of food resources is a major cause of species extinction. We tested the effects of habitat area, isolation and quality for the occurrence and population density of the endangered butterfly Polyommatus coridon. Polyommatus coridon larvae are monophagous on the plant Hippocrepis comosa, and both species are specialised on calcareous grassland, which is an endangered and highly fragmented habitat type in Germany.In 2001 we surveyed all known calcareous grasslands (n=298) around the city of Göttingen (Germany) to map the population size of H. comosa in these habitats. Further, habitat isolation (between‐patch distance: 70–7220 m) and habitat quality (cover of flowering plants, height of herb layer, percent bare ground, cover of shrub layer, wind protection, inclination) were quantified. Hippocrepis comosa occurred on only 124 fragments, which were then surveyed by 20 min transect counts for adult P. coridon in 2001 and 2002.Occurrence and population density of P. coridon were largely determined by the population size of its larval food plant, which was correlated with grassland area. Effects of habitat isolation and habitat quality on P. coridon populations contributed only little to the explanation.In conclusion, this monophagous habitat specialist depended on large habitats with large food plant populations to exist in viable populations. Habitat isolation and quality appear to contribute to occurrence and density patterns only in landscapes where these factors shift towards extremes, therefore general recommendations for conservation programs are difficult as they depend on regional distinctions.
Pituitary and autonomic responses to cold exposures in man
Authors: Leppäluoto J. , Pääkkönen T. , Korhonen I. , Hassi J. 
Published: July 2005

AbstractThis review presents hormonal responses to various cold exposures and their calorigenic effects in man and some animals. Previous studies in rats have shown that cold exposures activate the hypothalamic‐pituitary‐thyroid axis. Increased thyroid hormone concentrations lead to heat production via general stimulation of metabolism (obligatory thermogenesis) and possibly via activation of thyroid hormone receptors and uncoupling protein 1 (UCP 1) and deiodinase enzyme genes in the brown adipose tissue (BAT). In human subjects long‐term cold exposures do not seem to activate the pituitary‐thyroid axis, but rather accelerate the elimination of triiodothyronine (T3), leading to low serum concentrations of free T3 hormone. In corollary to this a hypothyreotic condition with increased serum thyroid‐stimulating hormone and impaired mood and cognitive performance can be observed after long‐term cold exposures such as wintering. During cold exposures the sympathetic nerve system is activated and noradrenaline is released to blood circulation and to BAT, where it leads to production of cAMP, lipolysis and free fatty acids. Free fatty acids open the mitochondrial proton channel protein in BAT. Protons enter the mitochondria and inhibit ATP synthesis (uncoupling). By this way energy is transformed into heat (facultatory or adaptive thermogenesis). In adult human subjects the amount of BAT is small and adaptive thermogenesis (non‐shivering thermogenesis) has a smaller role. UCP 1 with other uncoupling proteins may have other functions in the control of body weight, sugar balance and formation of reactive oxygen species.
Fuel selection in shivering humans
Authors: Weber J.‐M. , Haman F. 
Published: July 2005

AbstractHeat exchange has been thoroughly studied in cold‐exposed humans, but the metabolic substrates used for thermogenesis have received less attention. This review deals with oxidative fuel selection in shivering humans. Lipids provide most of the heat during low‐intensity shivering, whereas carbohydrates become dominant under more extreme cold conditions. The contribution from plasma glucose always remains minor, but muscle glycogen plays an important role during intense shivering. Whether the size of muscle glycogen stores influences endurance in the cold remains to be demonstrated. The fuel selection patterns of shivering and exercise are different, but the mechanisms underlying this difference have not been investigated. The simultaneous measurement of metabolic substrate oxidation and muscle fibre recruitment has allowed to characterize two different mechanisms of fuel selection in shivering humans: the recruitment of different pathways within the same fibres and of different fuel‐specific fibres within the same muscles. This suggests that muscle fibre composition of each individual may affect survival. Future research promises to provide a combination of theoretical advances on fundamental principles of fuel selection and applied strategies to manipulate fibre composition (through training) or fuel metabolism (through diet) to prolong human survival in cold environments.
A role for suppressed skeletal muscle thermogenesis in pathways from weight fluctuations to the insulin resistance syndrome
Authors: Dulloo A. G. 
Published: July 2005

AbstractAn impressive body of epidemiological evidence suggests that a history of large perturbations in body weight earlier in life, independently of excess weight, is a risk factor for later development of insulin‐related complications, namely central obesity, type 2 diabetes and cardiovascular disease. Such an increased risk has been reported in men and women who in young adulthood experienced weight fluctuations that involved weight recovery after weight loss caused by disease, famine or voluntary ‘yoyo’ dieting, and is particularly strong when the weight fluctuations occurred much earlier in life and are characterized by catch‐up growth after foetal and/or neonatal growth retardation. As the phase of weight recovery/catch‐up growth is associated with both hyperinsulinaemia and an accelerated rate for recovering fat mass (i.e. catch‐up fat), the questions arise as to whether, why and how processes that regulate catch‐up fat might predispose to hyperinsulinaemia and to insulin‐related diseases. In addressing these issues, this paper first reviews evidence for the existence of an adipose‐specific control of thermogenesis, whose suppression contributes to the phenomenon of catch‐up fat during weight recovery/catch‐up growth. It subsequently concentrates upon recent findings suggesting that: (i) such suppression of thermogenesis directed at catch‐up fat is accompanied by a redistribution of glucose from skeletal muscle to white adipose tissue, and (ii) substrate cycling between de novo lipogenesis and lipid oxidation can operate as a thermogenic effector in skeletal muscle in response to signalling interactions between leptin and insulin – two key ‘adiposity’ hormones implicated in the peripheral control of substrate metabolism. These new findings are integrated into the proposal that, in its ‘evolutionary adaptive’ role to spare glucose for rapid rebuilding of the fat stores, suppressed thermogenesis in skeletal muscle – via inhibition of substrate cycling between de novo lipogenesis and lipid oxidation – confers to the phase of weight recovery/catch‐up growth its high sensitivity towards the development of insulin resistance and hyperinsulinaemia, and hence towards diseases that are clustered around the insulin resistance syndrome.
Endocrine and signalling role of adipose tissue: new perspectives on fat
Authors: Trayhurn P. 
Published: July 2005

AbstractWhite adipose tissue (WAT) is now recognized as a major endocrine and secretory organ, releasing a wide range of protein factors and signals termed adipokines – in addition to fatty acids and other lipid moieties. A paradigm shift came with the discovery of leptin, a pleiotropic hormone which is a critical signal to the hypothalamus in the control of appetite and energy balance. A number of adipokines, including adiponectin, tumour necrosis factor‐alpha, interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10, monocyte chemoattractant protein‐1, macrophage migration inhibitory factor, nerve growth factor, vascular endothelial growth factor, plasminogen activator inhibitor‐1 and haptoglobin, are linked to inflammation and the inflammatory response. Obesity is characterized by a state of mild inflammation, and the expression and release of inflammation‐related adipokines generally rises as adipose tissue expands; a notable exception is adiponectin, with its anti‐inflammatory action, the levels of which fall. WAT may be the main site of inflammation in obesity, increased circulating levels of inflammatory markers reflecting spillover from an ‘inflamed’ tissue, leading to the obesity‐associated pathologies of type 2 diabetes and the metabolic syndrome. From the wide range of adipokines now identified, it is evident that WAT is highly integrated into overall physiological regulation, involving extensive crosstalk with other organs and multiple metabolic systems. Whether major changes in adipokine production in obesity, particularly of those factors linked to inflammation, are unique to this condition, or are a feature of all situations in which there are substantial increases in adipose mass (such as pregnancy, and pre‐hibernatory and pre‐migratory fattening) requires consideration.
Effect of atorvastatin and fluvastatin on the metabolism of midazolam by cytochrome P450 in vitro*
Authors: Mc Donnell C. G. , Shorten G. , Van Pelt F. N. A. M. 
Published: July 2005

SummaryWe have investigated the effects of the statins atorvastatin and fluvastatin on the cytochrome P450 3A4 enzyme (CYP 3A4)‐mediated metabolism of midazolam in vitro, using pooled human liver microsomes. Midazolam was metabolised by human hepatic microsomes with a Michaelis–Menten constant (Km) of 5.25 (SD 1.2) μmol.l−1. Atorvastatin was a moderate competitive inhibitor of CYP 3A4 with an inhibitory constant (Ki) of 12.4 (95% CI 4.65–20.06) μmol.l−1. Fluvastatin was a weak non‐competitive inhibitor of CYP 3A4 with a Ki of 94.3 (95% CI 55.01–133.5) μmol.l−1. Both atorvastatin and fluvastatin inhibit the CYP 3A4‐mediated metabolism of midazolam in vitro.
Lung recruitment during mechanical positive pressure ventilation in the PICU: what can be learned from the literature?
Authors: Halbertsma F. J. J. , Van Der Hoeven J. G. 
Published: July 2005

SummaryA literature review was conducted to assess the evidence for recruitment manoeuvres used in conventional mechanical positive pressure ventilation. A total of 61 studies on recruitment manoeuvres were identified: 13 experimental, 31 ICU, 6 PICU and 12 anaesthesia studies. Recruitment appears to be a continuous process during inspiration and expiration and is determined by peak inspiratory pressure (PIP) and positive end expiratory pressure (PEEP). Single or repeated recruitment manoeuvres may result in a statistically significant increase in oxygenation; however, this is short lasting and clinically irrelevant, especially in late ARDS and pneumonia. Temporary PIP elevation may be effective but only after PEEP loss (for example disconnection and tracheal suctioning). Continuous PEEP elevation and prone positioning can increasePao2significantly. Adverse haemodynamic or barotrauma effects are reported in various studies. No data exist on the effect of recruitment manoeuvres on mortality, morbidity, length of stay or duration of mechanical ventilation. Although recruitment manoeuvres can improve oxygenation, they can potentially increase lung injury, which eventually determines outcome. Based on the presently available literature, prone position and sufficient PEEP as part of a lung protective ventilation strategy seem to be the safest and most effective recruitment manoeuvres. As paediatric physiology is essentially different from adult, paediatric studies are needed to determine the role of recruitment manoeuvres in the PICU.
Differences between brain and rectal temperatures during routine critical care of patients with severe traumatic brain injury*
Authors: Childs C. , Vail A. , Protheroe R. , King A. T. , Dark P. M. 
Published: July 2005

SummaryTheoretical models suggest that small differences only exist between brain and body temperature in health. Once the brain is injured, brain temperature is generally regarded to rise above body temperature. However, since reports of the magnitude of the temperature gradient between brain and body vary, it is still not clear whether conventional body temperature monitoring accurately predicts brain temperature at all times. In this prospective, descriptive study, 20 adults with severe primary brain trauma were studied during their stay in the neurointensive care unit. Brain temperature ranged from 33.4 to 39.9 °C. Comparisons between paired brain and rectal temperature measurements revealed no evidence of a systematic difference [mean difference −0.04 °C (range −0.13 to 0.05 °C, 95% CI), p = 0.39]. Contrary to popular belief, brain temperature did not exceed systemic temperature in this relatively homogeneous patient series. The mean values masked inconsistent and unpredictable individual brain–rectal temperature differences (range 1.8 to −2.9 °C) and reversal of the brain‐body temperature gradient occurred in some patients. Brain temperature could not be predicted from body temperature at all times.
Fatal exacerbation of peripheral neuropathy during lamivudine therapy: evidence for iatrogenic mitochondrial damage
Authors: Fodale V. , Mazzeo A. , Praticò C. , Aguennouz M. , Toscano A. , Santamaria L. B. , Vita G. 
Published: July 2005

SummaryA 57‐year‐old man with mild neuropathy who was positive for hepatitis B and C viruses was treated with lamivudine 300 mg.day−1. After 3 months he presented with dysphonia and progressive muscle weakness. Subsequently, he developed tetraparesis followed by acute respiratory failure requiring mechanical ventilation, which was complicated by sudden cardiac arrest. After lamivudine was stopped, the neuropathy improved and respiratory capacity improved. Unfortunately, the patient died suddenly in spite of haemodynamic, ventilatory and metabolic support. Electrophysiological studies showed evidence of a sensory‐motor axonal neuropathy. Nerve biopsy, muscle biopsy, biochemistry and mitochondrial DNA molecular genetics suggested possible widespread iatrogenic mitochondrial damage. Mitochondrial DNA dysfunction could be a potential cause of the sudden cardiac arrest. Stopping lamivudine treatment sooner after the onset of peripheral neuropathy or its exacerbation is important as continued therapy could lead to acute respiratory failure requiring mechanical ventilation and intensive care unit admission.
Prophylactic percutaneous transtracheal catheterisation in the management of patients with anticipated difficult airways: a case series*
Authors: Gerig H. J. , Schnider T. , Heidegger T. 
Published: July 2005

SummaryPrimary tracheostomy under local anaesthesia is indicated in the management of an anticipated difficult airway in patients in whom less invasive procedures are expected to fail or have already failed. However, primary tracheostomy is a relatively complex procedure and places not inconsiderable stress on the patient. In a prospective study in our hospital over a period of 22 months, we were able to avoid primary tracheostomy in 11 patients with very difficult airways. All 11 patients were managed with prophylactically inserted transtracheal catheters and jet ventilation of the lungs. This ensured an adequate oxygen supply during tracheal intubation, and made overall patient management much easier. This method has established itself as a standard procedure in our hospital.
Large venous air embolism in the sitting position despite monitoring with transoesophageal echocardiography
Authors: Wong A. Y. C. , Irwin M. G. 
Published: July 2005

SummaryA 49‐year‐old male with neurofibromatosis type II was scheduled for posterior fossa craniotomy and excision of a right acoustic neuroma and placement of an auditory brainstem implant in the sitting position. Intra‐operatively, the patient was monitored with transoesophageal echocardiography which detected two major episodes of venous air embolism. Despite immediate treatment the patient's gas exchange progressively worsened during surgery and a chest X‐ray showed extensive bilateral pulmonary infiltrates. The patient developed acute respiratory distress syndrome and required inotropic support in the intensive care unit. Although transoesophageal echocardiography allowed rapid detection of venous air embolism, there was no evidence of therapeutic benefit.