Great Variation (great + variation)

Distribution by Scientific Domains


Selected Abstracts


Colloid Osmotic Pressure of Parenteral Nutrition Components and Intravenous Fluids

JOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 4 2001
Daniel L. Chan DVM
Abstract Objective:Parenteral nutrition is an important part of therapy for critically ill animals that cannot tolerate enteral feedings. It has been hypothesized that parenteral nutrition might also play a role in increasing colloid osmotic pressure (COP). The purpose of this study was to measure COP of various parenteral nutrition components and compare them to the COP of commonly used intravenous solutions. Design:Membrane colloid osmometry was used to measure the COP of parenteral nutrition components (lipids, Abstractamino acids, dextrose solutions) and of synthetic colloids, crystalloids, and blood products. Main Results:Parenteral nutrition components and all crystalloid solutions had COP measurements < 1 mm Hg. Great variation in COP was found in the different artificial colloids and blood products. The COP of the artificial colloids tested ranged from 32.7 ± 0.2 mm Hg for hetastarch to 61.7 ± 0.5 mm Hg for dextran 70. Conclusions:The results of this in vitro study suggest that parenteral nutrition does not directly contribute to an increase in oncotic pressure. Further studies are needed to determine whether parenteral nutrition may indirectly influence COP in vivo. Knowing the COP of a fluid, along with its other properties, is useful in making appropriate therapeutic decisions. [source]


Monitoring of resistance to spirodiclofen and five other acaricides in Panonychus citri collected from Chinese citrus orchards

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 9 2010
Jinfeng Hu
Abstract BACKGROUND: Citrus red mite, Panonychus citri (McGregor), is one of the most important pesticide-resistant pests in China. In order better to understand its resistance status, six populations of the mite were collected from Chinese citrus orchards for monitoring of resistance to spirodiclofen and another five acaricides. RESULTS: All the samples collected in the field in 2006 were susceptible to spirodiclofen. However, the LC50 values in populations sampled in 2009 ranged from 3.29 to 418.24 mg L,1 spirodiclofen, a 127-fold difference between the least and most sensitive populations. Compared with a susceptible strain, 50-fold and 90.8-fold resistance to spirodiclofen was detected in populations sampled from Pinghe and Fuzhou in 2009, as well as cross-resistance to spirotetramat. The LC50 values for abamectin, fenpropathrin, hexythiazox and pyridaben in the collected samples ranged from 0.041 to 3.52 mg L,1, from 23.91 to 696.16 mg L,1, from 13.94 to 334.19 mg L,1 and from 48.90 to 609.91 mg L,1 respectively. CONCLUSION: Great variations in resistance to the tested acaricides were observed among the sampled populations. The Pinghe population developed resistance to all the acaricides tested. The Jianning population was susceptible to most acaricides tested, except pyridaben. Resistance management strategies were conducted on the basis of these observations. Copyright © 2010 Society of Chemical Industry [source]


The Need to Rationalize and Prioritize Threatening Processes Used to Determine Threat Status in the IUCN Red List

CONSERVATION BIOLOGY, Issue 6 2009
MATT W. HAYWARD
carnivora; competencia; estatus de conservación; procesos amenazantes Abstract:,Thorough evaluation has made the International Union for Conservation of Nature (IUCN) Red List the most widely used and accepted authority on the conservation status of biodiversity. Although the system used to determine risk of extinction is rigorously and objectively applied, the list of threatening processes affecting a species is far more subjectively determined and has not had adequate review. I reviewed the threats listed in the IUCN Red List for randomly selected groups within the three most threatened orders of mammals: Artiodactyla, Carnivora, and Primates. These groups are taxonomically related and often ecologically similar, so I expected they would suffer relatively similar threats. Hominoid primates and all other terrestrial fauna faced similar threats, except for bovine artiodactyls and large, predatory carnivores, which faced significantly different threats. Although the status of bovines and hominoids and the number of threats affecting them were correlated, this was not the case for large carnivores. Most notable, however, was the great variation in the threats affecting individual members of each group. For example, the endangered European bison (Bison bonasus) has no threatening processes listed for it, and the lion (Panthera leo) is the only large predator listed as threatened with extinction by civil war. Some threatening processes appear spurious for the conservation of the species, whereas other seemingly important factors are not recorded as threats. The subjective nature of listing threatening processes, via expert opinion, results in substantial biases that may be allayed by independent peer review, use of technical manuals, consensus among multiple assessors, incorporation of probability modeling via decision-tree analysis, and adequate coordination among evaluators. The primary focus should be on species-level threats rather than population-level threats because the IUCN Red List is a global assessment and smaller-scale threats are more appropriate for national status assessments. Until conservationists agree on the threats affecting species and their relative importance, conservation action and success will be hampered by scattering scarce resources too widely and often by implementing conflicting strategies. Resumen:,La evaluación exhaustiva ha hecho que la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN) sea la autoridad más aceptada y ampliamente utilizada respecto al estatus de conservación de la biodiversidad. Aunque el sistema utilizado para determinar el riesgo de extinción es aplicado rigurosa y objetivamente, la lista de procesos amenazantes que afectan a las especies es determinado muy subjetivamente y no es revisado adecuadamente. Revisé las amenazas consideradas en la Lista Roja UICN para grupos seleccionados aleatoriamente en los tres órdenes de mamíferos más amenazados: Artyodactila, Carnivora y Primates. Estos grupos están relacionados taxonómicamente y a menudo son ecológicamente similares, así que esperaba que tuvieran amenazas relativamente similares. Los primates homínidos y toda la demás fauna terrestre enfrentan amenazas similares, excepto por los bovinos artiodáctilos y los carnívoros depredadores mayores, que enfrentan amenazas significativamente diferentes. Aunque el estatus de los bovinos y homínidos y el número de amenazas que los afectan estuvieron correlacionados, este no fue el caso para los carnívoros mayores. Sin embargo, lo más notable fue la gran variación en las amenazas que afectan a miembros individuales de cada grupo. Por ejemplo, no hay procesos amenazantes enlistados para el bisonte europeo (Bison bonasus), y el león (Panthera leo) es el único depredador mayor enlistado como amenazado de extinción por la guerra civil. Algunos procesos amenazantes parecen espurios para la conservación de las especies, mientras que otros factores aparentemente importantes no están registrados como amenazas. La naturaleza subjetiva de los procesos de enlistado, por medio de la opinión de expertos, resulta en sesgos sustanciales que pueden disiparse por la revisión independiente por pares, el uso de manuales técnicos, el consenso de múltiples asesores, la incorporación del modelado probabilístico mediante análisis de árboles de decisión y la adecuada coordinación entre evaluadores. El enfoque principal debería ser sobre amenazas a nivel de especies en lugar de amenazas a nivel de poblaciones porque la Lista Roja UICN es una evaluación global y las amenazas a menor escala son más apropiadas para evaluaciones nacionales de estatus. Hasta que los conservacionistas estén de acuerdo sobre las amenazas que afectan a las especies y su importancia relativa, las acciones de conservación y su éxito estarán obstaculizados por la dispersión demasiado amplia de recursos limitados y a menudo por la implementación de estrategias contrapuestas. [source]


Phylogeny of Rhus gall aphids (Hemiptera : Pemphigidae) based on combined molecular analysis of nuclear EF1, and mitochondrial COII genes

ENTOMOLOGICAL SCIENCE, Issue 3 2010
Zi-xiang YANG
Abstract Rhus gall aphids (Fordinae : Melaphidini) have a disjunct distribution in East Asia and North America and have specific host plant relationships. Some of them are of economic importance and all species form sealed galls which show great variation in shape, size, structure, and galling-site. We present a phylogeny incorporating ten species and four subspecies of Rhus gall aphids based on 1694 base pairs of nuclear elongation factor-1, (EF1,) and mitochondrial cytochrome oxidase subunit II (COII) DNA sequence data. The results suggest that Melaphidini is monophyletic and at the genus level, Schlechtendalia, Nurudea, and Floraphis were each monophyletic. Kaburagia and Meitanaphis were not monophyletic and therefore inconsistent with the current classification. The North American sumac gall aphid, Melaphis rhois, was most closely related to the East Asian Floraphis species, although this was poorly supported. The conservation of gall morphology with respect to aphid phylogeny rather than their host plants suggests that gall morphology is largely determined by the aphids. While there is no evidence of strict co-speciation between the aphids and their primary host plants, switching between recently diverged host plants may be involved in the speciation process in Melaphidini. [source]


Global patterns of genetic variation in plant species along vertical and horizontal gradients on mountains

GLOBAL ECOLOGY, Issue 2 2008
Takafumi Ohsawa
ABSTRACT Aim To understand global patterns of genetic variation in plant species on mountains and to consider the significance of mountains for the genetic structure and evolution of plant species. Location Global. Methods We review published studies. Results Genetic diversity within populations can vary along altitudinal gradients in one of four patterns. Eleven of 42 cited studies (26% of the total) found that populations at intermediate altitudes have greater diversity than populations at lower and higher altitudes. This is because the geographically central populations are under optimal environmental conditions, whereas the peripheral populations are in suboptimal situations. The second pattern, indicating that higher populations have less diversity than lower populations, was found in eight studies (19%). The third pattern, indicating that lower populations have lower diversity than higher populations, was found in 10 studies (24%). In 12 studies (29%), the intrapopulation genetic variation was found to be unaffected by altitude. Evidence of altitudinal differentiation was found in more than half of these studies, based on measurements of a range of variables including genome size, number of chromosomes or a range of loci using molecular markers. Furthermore, great variation has been found in phenotypes among populations at different altitudes in situ and in common garden experiments, even in cases where there was no associated variation in molecular composition. Mountains can be genetic barriers for species that are distributed at low elevations, but they can also provide pathways for species that occupy high-elevation habitats. [Correction added after publication 9 October 2007: ,less diversity' changed to ,greater diversity' in the second sentence of the Results section of the Abstract] Main conclusions Genetic diversity within populations can vary along altitudinal gradients as a result of several factors. The results highlight the importance of phenotypic examinations in detecting altitudinal differences. The influence of mountain ridges on genetic differentiation varies depending, inter alia, on the elevation at which the species occurs. Based on these findings, zoning by altitudes or ridges would be helpful for the conservation of tree populations with the onset of global warming. [source]


Anti-microbial hand washes for domestic use , their effectiveness in vitro and in normal use

INTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 3 2001
Kay Sharp
Abstract The killing or removal of microbes from the hands is a critical factor in food safety as many studies have shown the hands to be both an important source of microbes and powerful agents of cross-contamination in hospital and domestic situations. In response to this concern, a number of novel hand-washing products have appeared on the market. These products contain anti-microbial agents and claim to be more effective at removing bacteria than soap bars and conventional liquid soaps. This study attempts to test these claims by comparing the effectiveness of a conventional soap bar, a conventional liquid soap and an anti-microbial liquid soap containing triclosan. In vitro tests demonstrate that the anti-microbial liquid soap is more effective than conventional liquid soaps in reducing the viability of six bacterial species and that this effect is both time and dose dependent. However, when the three soaps were compared for their ability to reduce microbial counts on the hands no differences were observed between the three products. For all three soaps, counts after washing sometimes went up and sometimes down when compared with pre-wash counts. This was the case both when the soaps were used ,normally', that is, with great variation in the time taken, water and soap volumes used and method of washing and after a standardized, rigorous wash recommended in clinical situations. Furthermore, reduction in microbial counts from hands contaminated by handling raw meat was no greater for the anti-microbial than for the conventional liquid soap. [source]


Melanoma arising in a hairy nevus spilus

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2006
lgül Zeren-Bilgin MD
Cutaneous melanoma may develop de novo on normal skin or in contiguity with a potential melanocytic precursor. We report a 45-year-old man who presented with a recently developed nodule in a previously stable congenital nevus. Physical examination revealed a 10 × 18-cm lesion with speckled lentiginous pigmentation and terminal hairs on the lower back. A 2 × 2-cm suspicious nodule in the lesion was noted by the patient 2 months earlier. Histopathological evaluation of the nevus and the suspicious nodule revealed the characteristics of a melanocytic nevus and melanoma, respectively. It was interesting for the authors to observe terminal hairs in a lesion that was clinically ,speckled lentiginous' in appearance. This case report is a reminder that there may be great variation in the clinical appearance of nevus spilus, and thus dermatologists must be aware of these lesions as potential precursors of malignant melanoma. [source]


Early response as predictor of final remission in elderly depressed patients

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 11 2009
Rob M. Kok
Abstract Background Several studies have attempted to predict the final response or remission based on improvement during the early course of treatment of major depression. There is however a great variation in cut offs used to define early response and in the optimal week to predict final results. Objective To compare different cut offs at different time points early in the treatment of elderly depressed patients. Method A 12 week randomised, controlled trial in 81 elderly inpatients with DSM,IV major depression comparing venlafaxine with nortriptyline. At least 20, 25, 30 or 50% improvement was analysed after 1, 3 and 5 weeks using the Hamilton Depression Rating Scale and the Montgomery Asberg Depression Rating Scale. We plotted sensitivity against 1,specificity and calculated areas under the curve (AUCs). Results The highest percentage of correctly classified patients is found using at least 50% decrease as cut off in week 5, with acceptable sensitivity (81.8%) and specificity (87.4%). In week 5, the AUCs were 0.891 (95% CI 0.798,0.984) and 0.866 (95% CI 0.789,0.983) for the HAM-D and MADRS, respectively. Conclusions Combining the results from our study and the other studies addressing this issue, we suggest that the treatment should be changed in the elderly if after 3,4 weeks less than 30% improvement in depression score has been achieved. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Concentration compared with total urinary excretion of 11,17-DOA in cynomolgus monkey urine

JOURNAL OF MEDICAL PRIMATOLOGY, Issue 4 2009
J. Hau
Abstract Strees sensitive molecules exhibit great variation in concentration in the circulation and it may often be advantageous to quantify these in urine or feces rather than in serum or plasma. We advocate that all urine-or feces-should be collected, and that excretion of stress sensitive molecules should be expressed as amounts excreted per time unit per kg body-weight, rather than being expressed as concentrations in samples. Urine and feces excretion varies significantly within and between animals over time, which may render simple concentration measures of molecules of little biological relevance. [source]


Intended management of children with acute idiopathic thrombocytopenic purpura: A national survey

JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 1-2 2005
MK Marks
Objective: In Australia acute idiopathic thrombocytopenic purpura (ITP) is mainly treated by paediatricians (either general paediatricians or paediatric haematologists/oncologists). A survey was conducted to gauge the current practice of treating children with acute ITP in Australia. Methods: All practising Australian paediatricians registered by the Royal Australasian College of Physicians were surveyed regarding their intended management of children with acute ITP. The questionnaire, adapted from a study of paediatric haematologists/oncologists in North America, presented four clinical scenarios of children with acute ITP with a platelet count of 3000 × 109/L, with and without mucosal bleeding (wet and dry purpura, respectively). Questionnaires were returned by mail or filled in online at a dedicated webpage. Results: Five hundred and sixty-three of 1097 (51%) paediatricians responded to the survey. Data from 140 who had treated at least one child with ITP in the previous 12 months were analysed. Respondents indicated that children with acute ITP are usually or always hospitalised (58,92%) and that 48% would be given active treatment, even with dry purpura. Various regimens of i.v. immunoglobulin or corticosteroids are used when treatment is administered. In comparing Australian and North American management of acute ITP there were many similarities, although Australian paediatricians were less likely to arrange a bone marrow aspirate if corticosteroids were prescribed. Conclusions: There is great variation in the intended management of children with acute ITP in Australia. Previously published management recommendations regarding investigation and treatment have had little impact on intended practice. Prospective studies are required to evaluate hypotheses so as to produce evidence-based recommendations for treatment of patients with acute ITP. [source]


Medicaid matters: children's health and medicaid eligibility expansions

JOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 2 2002
Kristine A. Lykens
In the late 1980s, a series of federal laws were enacted which expanded Medicaid eligibility to more of the nation's children. States had a great amount of discretion in how fast and how far these expansions were implemented. As a result, there was great variation among the states in defining who was eligible for the program. This variation provides a rare opportunity to disentangle the effect of Medicaid from a child's socioeconomic status. Using data from the National Health Interview Survey, we address whether the Medicaid expansions improved the health and functional status of children. Econometric models were developed using fixed-effects regressions, and were estimated separately for white, black, and Hispanic children. White children experienced statistically significant reductions in acute health conditions and functional limitations. Black and Hispanic children showed some evidence of improved health conditions and functional status, but this evidence is inconclusive in the study sample. This may be due to differences in their access to appropriate health services or to the smaller sample size of minorities in each geographic area. The findings are also relevant to the implementation of the Children' Health Insurance Program (CHIP), the latest federal effort to expand access to health care to poor and near poor children. In many states, CHIP is being implemented in whole or in part through further Medicaid expansions. © 2002 by the Association for Policy Analysis and Management. [source]


Fruit physical, chemical and aromatic attributes of early, intermediate and late apricot cultivars

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2010
Riccardo Lo Bianco
Abstract BACKGROUND: In order to reach good fruit quality, apricots require a balance of sugars and acids as well as a strong apricot aroma. In this study, fruit quality of early, intermediate and late apricot cultivars was evaluated by measuring physical, chemical and olfactory attributes. Multivariate analysis of quality and aroma attributes was used to identify groups of similar cultivars and association with ripening season. RESULTS: Physical, chemical and aromatic attributes showed great variation among cultivars but no relation to ripening season. Aromatic profiles (34 volatiles) of fruit tissues indicated qualitative and quantitative differences among cultivars. Ninfa and Mandorlon were richest in aroma, with a prevailing fruity component; Goldrich and Orange Red were also highly aromatic, with all odour components well represented; Pinkot, Alba and Pellecchiella were lowest in aroma, with a prevailing grassy component. Linear functions including five volatiles (concentrations) and fruit diameter or six aromatic compounds (odour units) and peel colour were found to discriminate cultivars by ripening season. Principal component analysis individuated three groups of cultivars: Ninfa and Mandorlon with sweet and fruity-flavoured fruits; Bulida, Alba, Goldrich, Ouardy and Silvercot with large, acidic and well-coloured fruits; and Fracasso, Pellecchiella, Palummella and Pinkot with small and floral/grassy-flavoured fruits. CONCLUSION: In apricot, detailed analysis of the aromatic profile may represent an efficient tool for classification of genotypes by ripening season, and volatiles with relevant odour contribution may serve as quality markers for selecting towards an extended ripening season of best quality apricots. Copyright © 2010 Society of Chemical Industry [source]


The Great Divide Revisited: Ottoman and Habsburg Legacies on Transition

KYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 4 2007
Valentina Dimitrova-Grajzl
SUMMARY The former socialist countries of South East and Central Europe exhibit great variation in institutional quality. Unlike the sparse existing literature, I claim that the variation can be explained by the legacies of the Ottoman and Habsburg Empires. I identify historical legacies of the Empires, which have affected the current institutional quality of the successor states. I show empirically that the Empires' legacies are key determinants of institutional quality, and that the Habsburg successors have institutions that are more efficient in a market economy than the Ottoman successors. In contrast, I find an insignificant effect of socialism on institutional quality. [source]


Primary productivity can affect mammalian body size frequency distributions

OIKOS, Issue 2 2001
Birgitta Aava
Frequency distributions of mammal body sizes in large-scale assemblages have often been found to show a positive skew. In an attempt to explain this pattern, a model has been put forward which incorporates energetic constraints on fitness and thereby predicts optimal body sizes corresponding to the mode of the distribution. A key assumption of the model is that energy is unlimited. However, if energy is limited, the input of energy into a herbivorous mammal community should influence the shape of the frequency distribution. Thus, I propose that increases in primary productivity will decrease the variation of body size and increase the mean body size in a distribution. So, in low-productivity environments we should see a predominance of small-sized species, but with a great variation of body sizes due to limitations of resources (energy). I tested this hypothesis using the herbivorous mammal fauna (rodents, bats and marsupials) in seven biomes of Australia. Because herbivorous marsupials generally are fairly large-bodied while rodents and bats are small-sized and because marsupials also have a different mode of reproduction from placental mammals, the hypothesis was also tested on placental mammals and marsupials separately. There was no clear mode for the entire assemblage in any biome, but as primary productivity increased, the variation of body masses decreased and the mean body mass of the distribution increased. Body mass distributions of both placental mammals and marsupials displayed clear modes. Placental mammals also showed an increase in mean body mass. The variation in body mass of marsupials was highest for the intermediately productive biomes. Primary productivity does seem to have some effect on mammalian body mass in this case, but the results here need to be complemented with studies of other assemblages before any general conclusions can be drawn. It is also important to distinguish which taxa are affected in a heterogeneous assemblage like the Australian herbivorous mammal fauna. [source]


Fetal alcohol syndrome and developing craniofacial and dental structures , a review

ORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 4 2006
LB Sant'Anna
Structured abstract Authors ,, Sant'Anna LB, Tosello DO Objectives ,, Fetal alcohol syndrome (FAS) is a collection of signs and symptoms seen in children exposed to alcohol in the prenatal period. It is characterized mainly by a distinct pattern of craniofacial malformations, physical and mental retardation. However, with the increased incidence of FAS, there is a great variation in the clinical features of FAS. Design ,, Narrative review. Results ,, This review describes data from clinical and experimental studies, and in vitro models. Experimental studies have shown that alcohol has a direct toxic effect on the ectodermal and mesodermal cells of the developing embryo, particularly in the cells destined to give rise to dentofacial structures (i.e. cranial neural crest cells). Other effects, such as, abnormal pattern of cranial and mandibular growth and altered odontogenesis are described in detail. The exact mechanism by which alcohol induces its teratogenic effects remains still unknown. The possible mechanisms are outlined here, with an emphasis on the developing face and tooth. Possible future research directions and treatment strategies are also discussed. Conclusion ,, Early identification of children affected by prenatal alcohol exposure leads to interventions, services, and improved outcomes. FAS can be prevented with the elimination of alcohol consumption during pregnancy. We need to provide education, target high-risk groups, and make this issue a high priority in terms of public health. [source]


Development of a strategy for transgenic studies and monitoring of transgene expression in two closely related Moricandia species possessing a C3 or C3,C4 intermediate photosynthetic phenotype

PHYSIOLOGIA PLANTARUM, Issue 1 2003
Vera Thole
In order to establish a model system for comparative studies of C3 and C3,C4 intermediate photosynthesis, the development of efficient transformation systems and the monitoring of transgene behaviour and stability were carried out in two closely related Moricandia species (Brassicaceae): the C3,C4 photosynthetic intermediate species M. arvensis and the C3 species M. moricandioides. In this study the green fluorescent protein (gfp) reporter gene was used as a vital marker gene while the use of the , -glucuronidase (gusA) gene was based on the highly sensitive detection of its activity. For Agrobacterium -mediated transformation of leaf explants, a cauliflower mosaic virus 35S promoter-driven, modified version of gfp, the mgfp5-ER gene and the gusA gene, respectively, were introduced into the new dual binary transformation vector system pGreen/pSoup (Hellens et al. 2000, Plant Mol Bio 42: 819,832). GFP5 produced bright-green fluorescence in transformed tissues that was distinctly detected 5,12 days following transformation in developing calli of the two species. Visual screening, combined with antibiotic selection, enabled early and easy identification of transformation events and contributed to improvements in the transformation strategies. Transgene integration studies demonstrated that mgfp5-ER was inserted with low copy number in the M. arvensis plant lines and the transgene was transmitted in a Mendelian fashion to T1 and T2 progenies. GFP5 expression levels in a population of 100 independent primary transformed M. arvensis plant lines (T0) showed great variation between transformation events (coefficient of variation of 108%). The mgfp5-ER or gusA reporter genes were expressed in 90,95% of the kanamycin-resistant M. arvensis plant lines and in up to 98% of the independent M. moricandioides plant lines. [source]


Estimation of the relative antiinflammatory efficacies of six commercial preparations of Harpagophytum procumbens (Devil's Claw)

PHYTOTHERAPY RESEARCH, Issue 3 2010
Nassima Abdelouahab Ouitas
Abstract The current work compared the relative efficacies of six commercial formulations of H. procumbens. Each formulation was assayed for the content of harpagoside (1), harpagide (2), verbascoside (3) and 8- O-p -coumaroyl harpagide (4) and, based on the recommended dosages, the total daily amounts were determined and used to establish anti-/proinflammatory (A/P) factors. The formulations were compared using ex vivo porcine skin for their activities towards COX-2 by Western blotting. The results showed great variation in the amounts of compounds 1,4 within the six formulations examined. The relative proportions of 1,4 also varied widely between the products and this inconsistency was reflected in the A/P factors, which correlated with the COX-2 expression (R2 = 0.9496). Although the data support the beneficial antiinflammatory effects from the use of some of the brands tested, others would appear potentially to exacerbate inflammation. To conclude, a ratio based upon the amount and relative proportions of anti- and proinflammatory compounds can be used to predict relative antiinflammatory properties. Also, with access to a diversity of ostensibly similar commercial products, the patient may experience varying therapeutic responses. Finally, current pharmacopoeia monographs, which are generally concerned with a minimum harpagoside content, are inadequate for ensuring the quality of products based on H. procumbens. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Lead,yeast hexokinase interaction: modifications to protein structure caused by the metal

POLYMER INTERNATIONAL, Issue 7 2001
C Teijón
Abstract The interaction between lead and yeast hexokinase has been studied. Lead provokes a large variation in the aggregation state of the protein, forming bigger structures of high molecular mass. This phenomenon is characterized by a small modification in the tridimensional structure and a great variation in the secondary structure. There is a loss in ,-helix which is compensated by an enhancement in ,-sheet. The polypeptide chain is more stable in the ,-sheet structure corresponding to the aggregate forms. During this change the enzyme maintains a high level of activity in the monomer and also in the aggregate form. This implies that the enzyme function is not greatly affected by the change, and active sites are retained without important modifications. According to kinetic measurements the ATP site is more affected than the glucose site. There is a mixed type inhibition with a main competitive component when glucose acts as a variable substrate. © 2001 Society of Chemical Industry [source]


Gross Morphometry of the Bovine Placentome during Gestation

REPRODUCTION IN DOMESTIC ANIMALS, Issue 6 2001
RA Laven
Forty-seven pregnant uteri were collected from an abattoir at eight chronological stages of gestation. Assessments were made of placentome number, weight, length shape and ratio of foetal to maternal tissue by weight. The study showed that there was a great variation in number, size, weight and shape of placentomes. There was no significant change in the total number of placentomes during gestation. Both mean weight and length increased significantly during gestation, but there was a significant change in the relationship between the two as gestation progressed. There was no correlation between the number of placentomes and the mean weight or length of the placentomes. The development of the placenta in the non-pregnant horn was significantly different from that of the pregnant horn, with fewer, smaller, lighter placentomes. However, there was no evidence that placentome development in the non-pregnant horn was affected by placentome development in the pregnant horn. The proportion of the placentome that was maternal tissue increased during gestation, but there was no significant effect of placentome number, or individual placentome weight or length on this proportion. Two placentome shapes were identified, but no effect on foeto-maternal proportion or relationship between shape and total placentome number or weight was identified. [source]


Lung cancer: Progress in diagnosis, staging and therapy

RESPIROLOGY, Issue 1 2010
Stephen G. SPIRO
ABSTRACT Lung cancer remains one of the greatest medical challenges with nearly 1.5 million new cases worldwide each year and a growing tobacco epidemic in the developing world. This review summarizes briefly the current status in growing areas of clinical research. The value of screening for early disease is not yet established and trials to see if mortality can be improved as a result are in progress. Better and more accurate staging will both streamline investigation and prove cost-effective once ultrasound-guided biopsy and aspiration of mediastinal nodes become universally accepted. This, allied to the new staging classification, will improve selection of cases for surgery, intensive multimodality therapy and for adjuvant treatment postoperatively. Much still needs to be done to refine staging as within a particular stage group, the outcome shows great variation. More information is needed on the genetic make-up in some groups of tumours and not just their size; that is, more biological data on tumour growth patterns are likely to be at least as discriminating. The place of the stem cell theory of tumorigenesis is also explored in this paper. Finally, targeted therapy for advanced non-small-cell lung cancer is highlighted as a development with early promise, but still much clarification is required, before it can be considered as a universal approach in late disease. [source]


Informed consent for epidural analgesia in labour: a survey of UK practice,

ANAESTHESIA, Issue 2 2009
J. V. Middle
Summary Anaesthetists are legally obliged to obtain informed consent before performing regional analgesia in labour. A postal survey of consultant-led UK anaesthetic units was performed in September 2007 to assess practice regarding obtaining informed consent before inserting an epidural, and documentation of the risks discussed. The response rate was 72% (161/223). There was great variation between units regarding which risks women were informed about and the likely incidence of that risk. One hundred and twenty-three respondents out of 157 providing an epidural service (78%) supported a national standardised information card endorsed by the Obstetric Anaesthetists' Association, with all the benefits and risks stated, to be shown to all women before consenting to an epidural in labour. [source]


Newly qualified teachers' learning related to their use of information and communication technology: a Swedish perspective

BRITISH JOURNAL OF EDUCATIONAL TECHNOLOGY, Issue 5 2006
Sven B. Andersson
This qualitative study focuses on newly qualified teachers' use of information and communication technology (ICT) as a tool for meeting the challenges of their everyday work. The overarching aim is to investigate whether they can contribute to new knowledge about learning in ICT contexts. Theoretical points of departure concern the changeable nature of learning in situations where ways of communicating knowledge and skills are changed. The study draws upon interviews and observations. The findings show intersections picturing the new technique as partly changing the circumstances for teaching, learning and collaboration between colleagues. The new teachers' utterances show that ICT utilisation is extensive and exhibits great variation both among female and among male participants. Boundary-crossing changes become visible in the collaboration between more experienced teachers and those who are newly qualified, especially when they work on a common development project. However, there are relatively few teachers who bring up active ICT use in connection with pupils' learning. Changed roles because of ICT competence raise questions about the importance of systematic ICT features within teacher education. Many of the newly qualified teachers wish they had more knowledge about ICT and related techniques. Another question is whether newly qualified teachers who show interest in using the technique can take on the role as agents of change in their active and creative use of ICT. [source]


Incidence and mortality rates for colorectal cancer in Puerto Rico and among Hispanics, non-Hispanic whites, and non-Hispanic blacks in the United States, 1998-2002

CANCER, Issue 13 2009
Marievelisse Soto-Salgado MS
Abstract BACKGROUND: Colorectal cancer (CRC) is the second most commonly diagnosed cancer in Puerto Rico (PR). In the United States, the incidence and mortality rates of CRC have great variation by sex and race/ethnicity. Age-standardized incidence and mortality rates of CRC in PR were assessed and compared with the rates among US Hispanics (USH), non-Hispanic whites (NHW), and non-Hispanic blacks (NHB) in the United States for the period from 1998 through 2002. Incidence and mortality trends and relative differences among racial/ethnic groups by sex and age were determined. METHODS: Age-standardized rates using the world standard population (ASR[World]) were based on cancer incidence and mortality data from the PR Central Cancer Registry and from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program using the direct method. The annual percentage changes (APC) and relative risks (RR) were calculated using Poisson regression models. RESULTS: During 1998 through 2002, the APC of CRC incidence and mortality increased for men in PR, whereas descending trends were observed for other racial/ethnic groups. Overall period rates indicated that, in both sexes, Puerto Ricans had CRC incidence and mortality rates similar to those for USH, but their rates were lower than those for NHW and NHB. However, Puerto Rican men and women ages 40 years to 59 years had the greatest risk of incidence and mortality compared with their USH counterparts. CONCLUSIONS: Areas of concern include the increasing trends of CRC in PR and the higher burden of the disease among young Puerto Ricans compared with the USH population. The authors concluded that further research should be performed to guide the design and implementation of CRC prevention and education programs in PR. Cancer 2009. © 2009 American Cancer Society. [source]


The bone,metal interface of defect and press-fit ingrowth of microwave plasma-chemical vapor deposition implants in the rabbit model

CLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2005
Stephan Rupprecht
Abstract Purpose: The histological differences between the defect and contact areas of the implant surface to bone were tested in 35 New Zealand White rabbits in a standardized model. Microwave plasma chemical vapor-coated implant probes were tested in control and uncoated materials. Material and methods:, In each femur of 35 rabbits, cylindrical implant rods with a planed side were inserted. Three groups, divided in coated and uncoated material at half, were observed 42, 84 and 168 days. The probes were examined histologically for bone,implant contact in the curved and plane (defect area) sides. Results: Generally the bone,implant contact seems to be nearly constant in time in the curved area of coated and uncoated probes. Here the implant was inserted in the press-fit mode. Diamond-coated probes showed similar bone,implant contact (51.9% (42 days), 62.5% (84 days), 56.1% (168 days)) compared to uncoated material (56.2%, 65.4%, 62.9%). The defect area (plane side) had no bone,implant contact at the time of insertion and showed increasing values on longer observation times with only significant differences in the 42-day group between coated (17.85%, 35.2%, 47.7%) and uncoated materials (35.5%, 40.55%, 51.81%). Conclusion: The evaluation of the curved side of the implant probe showed no great variation of bone,implant contact within the described observation times. This model simulates the usual implant insertion situation. The diamond-coated material becomes osseointegrated at a later time point. The bone,implant contact was only statistically relevant in one group in comparison to uncoated material. Résumé Les différences histologiques entre la lésion et les aires de contact de la surface implantaire à l'os ont été testées chez 35 lapins blancs de Nouvelle-Zélande dans un modèle standardisé. Des sondes implantaires recouvertes d'une vapeur chimique de plasma par micro-ondes ont été testées par rapport à du matériel non-recouvert. Dans chaque fémur des 35 lapins, des baguettes implantaires cylindriques avec un côté plat ont été insérées. Trois groupes, divisés en matériel couvert et non-couvert à moitié ont été observés après 42, 84 et 168 jours. Les sondes ont été examinées histologiquement pour le contact os-implant dans les sites courbe et plat (aire de la lésion). Généralement le contact os-implant semblait constant dans la durée dans la zone courbe des sondes couvertes et non-couvertes. Ici l'implant a été inséré par la méthode de pressé-fixé (=fit après insertion). Les sondes recouvertes de diamant montraient un contact os-implant semblable (52%à 42 J, 63%à 84 J et 56%à 168 J) comparées au matériel non-recouvert (56%, 65%, 63%). L'aire de la lésion (partie plate) n'avait pas de contact os-implant au moment de l'insertion et montrait des valeurs grandissantes avec le temps avec seulement des différences significatives dans les groupes à 42 jours entre le matériel recouvert (18%, 35% et 48%) et le non-recouvert (36%, 41% et 52%). L'évaluation du côté arrondi de la sonde implantaire ne montrait pas de grande variation dans le contact os-implant dans les temps d'observation décrits. Ce modèle simule la situation d'insertion implantaire usuelle. Le matériel recouvert de diamant devient ostéoïntégré plus tardivement. Le contact os-implant n'était statistiquement valable que dans un groupe en comparaison avec le matériel non-recouvert. Zusammenfassung Ziel: Mit einem standartisierten Modell untersuchte man an 35 weissen New Zealand Kaninchen die histologischen Unterschiede zwischen in direktem Kontakt mit dem Implantat stehendem Knochen und Defektstellen. Testimplantate, die mit Diamant beschichtet worden sind, verglich man mit unbeschichtetem Material als Kontrolle. Material und Methode: In jeden Femur der 35 Kaninchen inserierte man zylindrische Implantate, die auf einer Seite abgeplattet waren. Man beobachtete drei Gruppen, je hälftig unterteilt in beschichtete und unbeschichtete Implantate, während 42, 84 und 168 Tagen. Die Blockbiopsien wurden in der runden und abgeflachten (Defektzone) Region histologisch auf ihren Implantat-Knochen-Kontakt hin untersucht. Resultate: Allgemein stellte man fest, dass der Knochen-Implantat-Kontakt während der ganzen Beobachtungszeit in der runden Region der beschichteten und unbeschichteten Implantate ziemlich konstant zu bleiben scheint. Die Implantate sind eingeklopft worden. Die diamantbeschichteten Prüfkörper zeigten einen ähnlichen Knochen-Implantat-Kontakt (51.9% (42d), 62.5% (84d), 56.1% (168d)) wie die unbeschichteten Prüfkörper (56.2%, 65.4%, 62.9%). Die Defektzonen (abgeflechte Stellen) hatten zum Zeitpunkt der Implantation natürlich keinen Kontakt zum Knochen, zeigten aber während der Beobachtungszeit zunehmend Kontakt. Einzig nach 42 Tagen zeigten sich zwischen den beschichteten (17.85%, 35.2%, 47.7%) und den unbeschichteten Implantaten (35.5%, 40.55%, 51.81%) signifikante Unterschiede. Zusammenfassung: Innerhalb der umschriebenen Beobachtungszeit zeigte die Untersuchung der runden Seite der Implantate keine grossen Unterschiede bei der Ausdehnung der Kontaktflächen zum Knochen. Dieses Modell empfindet die übliche Implantationssituation nach. Das mit Diamant beschichtete Material wird zu einem etwas späteren Zeitpunkt osseointegriert. Die Unterschiede im Knochen-Implantat-Kontakt waren im Vergleich mit dem unbeschichteten Material nur in einer Gruppe statistisch gesehen von Bedeutung. Resumen Propósito: Se probaron las diferencias histológicas entre los defectos y las áreas de contacto de la superficie del implante al hueso en 35 conejos blancos de Nueva Zelanda en un modelo estandarizado. Se investigaron implantes de prueba cubiertos de plasma de vapor químico de microonda frente a material sin cubierta como control. Material y Métodos: Se insertaron en cada fémur de 35 conejos barras cilíndricas de implantes con un lado plano. Se observaron tres grupos divididos en material cubierto y no cubierto a la mitad durante 42, 84 y 168 días. Las pruebas se examinaron histológicamente para contacto hueso-implante en los lados curvado y plano (área de defecto). Resultados: Generalmente el contacto hueso implante suele ser constante en el tiempo en el área curvada de las pruebas cubiertas y no cubiertas. Aquí el implante se insertó en el modo press-fit. Las pruebas cubiertas de diamantes mostraron un contacto hueso implante similar (51.9% (42d), 62.5% (84d), 56.1% (168)) comparados con el material no cubierto (56.2%, 65.4%, 62.9%). El área de defecto (lado plano) no tuvo contacto hueso implante en el momento de la inserción y mostró valores crecientes en periodos mas largos de observación con solo diferencias significativas en el grupo del día 42 entre materiales cubiertos (17.85, 32.2%, 47%) y no cubiertos (35.5%, 40.55%, 51.81%). Conclusión: La evaluación del lado curvado del implante de prueba no mostró una gran variación del contacto hueso implante dentro de los tiempos de observación descritos. Este modelo simula la situación usual de inserción del implante. El material cubierto de diamante se osteointegra en un momento posterior. El contacto hueso implante fue solo estadísticamente relevante en un grupo en comparación con el material no cubierto. [source]


Horseshoe kidney transplantation: an overview

CLINICAL TRANSPLANTATION, Issue 6 2000
Otto B Stroosma
The horseshoe kidney is the most common anatomical renal variation. It represents a fusion anomaly, mainly at the lower poles, occurring between the 4th and 6th week of gestation. Horseshoe kidneys display a great variation in origin, number and size of the vasculature. Transplantation of these deviant kidneys can be done en bloc or they can be split into two halves and transplanted into two recipients, depending on the number of vessels and the anatomy of the urinary collecting system. A literature review reveals 31 case histories, published between 1975 and 1998. Of these 21 were transplanted into 38 recipients after division and ten were implanted en bloc. Nineteen grafts (41%) showed immediate function and 21 grafts (46%) showed delayed function. Thrombosis and acute rejection, leading to non-function was seen in six grafts (13%). The overall success rate was 87% with a mean follow-up of 22 months. The results of horseshoe kidney transplantation are good, provided that attention is paid to certain technical details. Because of donor scarcity, horseshoe kidneys should be used for transplantation. [source]


Incidence and geographical distribution of sudden infant death syndrome in relation to content of nitrate in drinking water and groundwater levels

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2001
M. George
Background Previous studies indicate that the enteral bacterial urease is inhibited in victims of sudden infant death syndrome (SIDS). One possible inhibitor of this bacterial activity is nitrate. If ambient pollution by nitrate is involved in the etiology of SIDS only a fraction of the nitrate concentration not infrequently found in drinking water would be enough for this inhibition. Methods Occurrence of SIDS (n = 636) in Sweden during the period 1990 through 1996 were analysed regarding geographical and seasonal distribution in relation to the nitrate concentration in drinking water and changes in the groundwater level. Results Both the birth rate and the incidence of SIDS decreased during the study period. One quarter of the municipalities constituting 11% of the population had no cases, the maximum incidence being 6·5 per 1000 live births. Seasonality: The northernmost parts of the country had its highest incidence when the rest of the country had its lowest incidence, and the occurrence of individual deaths was associated with the recharge of groundwater which increases its nitrate content. The local incidence of SIDS was correlated (rs = 0·34,0·87) to maximally recorded concentrations of nitrate in drinking water. Conclusions The seasonal distribution of SIDS was widely different from the south to the north of the country and seems to be associated with differences in the groundwater level changes subsequent to precipitation, frost penetration, and melting of snow. Use of drinking water with high peak concentrations or great variations in nitrate concentration was correlated to the incidence of SIDS. [source]


Breeding success in a Houbara Bustard Chlamydotis [undulata] macqueenii population on the eastern fringe of the Jungar Basin, People's Republic of China

IBIS, Issue 2 2002
O. Combreau
Nesting success and chick survival of a migratory population of Houbara Bustard Chlamydotis [undulata] macqueenii were studied during three consecutive years (1998,2000) in the Xinjiang province of north-west China. A total of 45 nests was monitored and 85 broods comprising 227 chicks were captured, of which 82 chicks were radio-tracked. Start of laying varied between 6 and 17 April between years but the laying mode fell consistently between 26 and 30 April. Mean clutch size was 4.0 (sd = 0.8) (range 2,6) for early clutches and 3.3 (sd = 1.1) for late clutches (range 2,5). The average nesting success was 0.588 (sd = 0.270) but great variations were observed between years ,0.882 in 1998, 0.530 in 1999 and 0.351 in 2000. This was related to increased predation in 1999 and 2000, which is reflected by increased predator density (chiefly Corsac Fox Vulpes corsac and Long-legged Buzzards Buteo rufinus). The overall hatchability, defined as the proportion of eggs hatched in successful nests was 0.839 sd = 0.238). The average brood size at hatching varied from 2.9 (sd = 0.8) to 3.3 (sd = 0.9) according to years, and no significant decrease in brood size was observed in the first 5 days post-hatching. In 1999 and 2000 the brood size diminished sharply (14% and 27%, respectively) in prefledging chicks. A further severe decrease (37%) was observed in fledglings in 2000, probably due to predation by raptors. For the 3 years of the study, a successful female Houbara would bring on average 2.3 (sd = 0.9) chicks to fledging and would have lost 30.2% (sd = 14.9%) of its brood to adversity during the rearing process. The proportion of females that lost their entire brood was 0.181 in 1998, 0.708 in 1999 and 0.453 in 2000. For the 3 years of the study, only 55.3% (sd = 26.3%) of the females hatching eggs brought chicks to fledging. The overall chick production was 0.827 per breeding female per year and the probability of an egg laid producing a fledgling of 8 weeks old was 0.190. [source]


Morphology and ultrastructure of the female accessory sex glands in various crickets (Orthoptera, Saltatoria, Gryllidae)

MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE IN BERLIN-DEUTSCHE ENTOMOLOGISCHE ZEITSCHRIFT, Issue 2 2002
Robert Sturm
Abstract In the present study, the morphology and ultrastructure of the accessory sex glands in females of the three cricket species Teleogryllus commodus, Gryllus bimaculatus, and Gryllus assimilis were subject to a detailed comparison. Within the observed crickets, the pairy glands are uniformly located in the 6th and 7th abdominal segment, joining the genital chamber lateral to the terminal papilla. Each gland is composed of an apical region (R3), consisting of the end tubules which produce the main amount of secretion, a middle region (R2) storing and leading the secretion to the orifice, and a basal region (R1) defining the orifice and most basal part of the gland. Concerning the size, number of ramifications, and length/width ratio, the investigated organs are marked by great variations among the species, ranging from anisometric glands (length/width < or > 1) with low number of ramifications in Teleogryllus commodus and Gryllus assimilis to nearly isometric glands with very numerous (up to 30) ramifications in Gryllus bimaculatus. The morphology of the respective glands is uniformly expressed by an epithelium composed of a basal lamina, one layer of gland cells, and a luminal, duct-less cuticular intima forming specific spines and hair-like processes. The ultrastructure of single gland cells is marked by a basal region with a large elliptic nucleus and intracellular cisternae formed by deep invaginations of the basal cell membrane. The apical part contains numerous lipid- and protein-forming compartments, mitochondria of cristae type, vesicles, and lipid drops. The apical cell surface is enlarged by forming a dense layer of microvilli. The lipophilic secretion produced by the glands is thought to be used as a lubricant in the ovipositor during egg-laying. [source]


Contact Sensitization in 1094 Children Undergoing Patch Testing over a 7-Year Period

PEDIATRIC DERMATOLOGY, Issue 1 2005
Stefania Seidenari M.D.
However, because exposure to sensitizing agents varies rapidly, it is of utmost importance to perform a periodic evaluation of patch test results. Our purpose was to compare our data on contact sensitization in children during the past 7 years to our previous 1988,1994 findings, in order to identify emerging allergens and update our pediatric series. From 1995 to 2001, 1094 consecutive children were examined. Of these, 997 patients were patch tested with our pediatric series, which includes 30 allergens, whereas 97 underwent patch testing with 46 allergens. A total of 570 children proved allergic (52.1%). The highest sensitization rate was observed in children under 3 years of age. No differences between atopic dermatitis patients and nonatopic ones were observed in the sensitization rate. Neomycin, nickel, wool alcohols, thimerosal, and ammoniated mercury gave most of the positive responses. With respect to 1988,1995 data, allergy to substances such as neomycin, nickel, wool alcohols, thimerosal, ammoniated mercury, propolis, potassium dichromate, and thiuram mix proved more frequent. In conclusion, as sensitization rates to different allergens show great variations over time, periodic evaluations of patch test results in children is necessary in order to update the test trays. [source]


The apparent temperature response of leaf respiration depends on the timescale of measurements: a study of two cold climate species

PLANT BIOLOGY, Issue 2 2008
D. Bruhn
Abstract Productivity and climate models often use a constant Q10 for plant respiration, assuming tight control of respiration by temperature. We studied the temperature response of leaf respiration of two cold climate species (the Australian tree Eucalyptus pauciflora and the subantarctic megaherb Pringlea antiscorbutica, both measured in a field setting) on a short timescale (minutes) during different times within a diel course, and on a longer timescale, using diel variations in ambient temperature. There were great variations in Q10 depending on measuring day, measuring time and measuring method. When Q10 was calculated from short-term (15 min) manipulations of leaf temperature, the resulting values were usually markedly smaller than when Q10 was calculated from measurements at ambient leaf temperatures spread over a day. While for E. pauciflora, Q10 estimates decreased with rising temperature (corroborating the concept of a temperature-dependent Q10), the opposite was the case for P. antiscorbutica. Clearly, factors other than temperature co-regulate both leaf respiration rates and temperature sensitivity and contribute to diel and seasonal variation of respiration. [source]