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ORIGINAL ARTICLE (original + article)
Selected AbstractsORIGINAL ARTICLE: Genetics, adaptation, and invasion in harsh environmentsEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2010Richard Gomulkiewicz Abstract We analyze mathematical models to examine how the genetic basis of fitness affects the persistence of a population suddenly encountering a harsh environment where it would go extinct without evolution. The results are relevant for novel introductions and for an established population whose existence is threatened by a sudden change in the environment. The models span a range of genetic assumptions, including identical loci that contribute to absolute fitness, a two-locus quantitative genetic model with nonidentical loci, and a model with major and minor genes affecting a quantitative trait. We find as a general (though not universal) pattern that prospects for persistence narrow as more loci contribute to fitness, in effect because selection per locus is increasingly weakened with more loci, which can even overwhelm any initial enhancement of fitness that adding loci might provide. When loci contribute unequally to fitness, genes of small effect can significantly reduce extinction risk. Indeed, major and minor genes can interact synergistically to reduce the time needed to evolve growth. Such interactions can also increase vulnerability to extinction, depending not just on how genes interact but also on the initial genetic structure of the introduced, or newly invaded, population. [source] ORIGINAL ARTICLE: Propensity of marine reserves to reduce the evolutionary effects of fishing in a migratory speciesEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 3 2009Erin S. Dunlop Abstract Evolutionary effects of fishing can have unwanted consequences diminishing a fishery's value and sustainability. Reserves, or no-take areas, have been proposed as a management tool for reducing fisheries-induced selection, but their effectiveness for migratory species has remained unexplored. Here we develop an eco-genetic model to predict the effects of marine reserves on fisheries-induced evolution under migration. To represent a stock that undergoes an annual migration between feeding and spawning grounds, we draw model parameters from Atlantic cod (Gadus morhua) in the northern part of its range. Our analysis leads to the following conclusions: (i) a reserve in a stock's feeding grounds, protecting immature and mature fish alike, reduces fisheries-induced evolution, even though protected and unprotected population components mix on the spawning grounds; (ii) in contrast, a reserve in a stock's spawning grounds, protecting only mature fish, has little mitigating effects on fisheries-induced evolution and can sometimes even exacerbate its magnitude; (iii) evolutionary changes that are already underway may be difficult to reverse with a reserve; (iv) directly after a reserve is created or enlarged, most reserve scenarios result in yield losses; and (v) timescale is very important: short-term yield losses immediately after a reserve's creation can give way to long-term gains. [source] ORIGINAL ARTICLE: Implications of fisheries-induced evolution for stock rebuilding and recoveryEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 3 2009Katja Enberg Abstract Worldwide depletion of fish stocks has led fisheries managers to become increasingly concerned about rebuilding and recovery planning. To succeed, factors affecting recovery dynamics need to be understood, including the role of fisheries-induced evolution. Here we investigate a stock's response to fishing followed by a harvest moratorium by analyzing an individual-based evolutionary model parameterized for Atlantic cod Gadus morhua from its northern range, representative of long-lived, late-maturing species. The model allows evolution of life-history processes including maturation, reproduction, and growth. It also incorporates environmental variability, phenotypic plasticity, and density-dependent feedbacks. Fisheries-induced evolution affects recovery in several ways. The first decades of recovery were dominated by demographic and density-dependent processes. Biomass rebuilding was only lightly influenced by fisheries-induced evolution, whereas other stock characteristics such as maturation age, spawning stock biomass, and recruitment were substantially affected, recovering to new demographic equilibria below their preharvest levels. This is because genetic traits took thousands of years to evolve back to preharvest levels, indicating that natural selection driving recovery of these traits is weaker than fisheries-induced selection was. Our results strengthen the case for proactive management of fisheries-induced evolution, as the restoration of genetic traits altered by fishing is slow and may even be impractical. [source] ORIGINAL ARTICLE: Probability of emergence of antimalarial resistance in different stages of the parasite life cycleEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 1 2009Wirichada Pongtavornpinyo Abstract Understanding the evolution of drug resistance in malaria is a central area of study at the intersection of evolution and medicine. Antimalarial drug resistance is a major threat to malaria control and directly related to trends in malaria attributable mortality. Artemisinin combination therapies (ACT) are now recommended worldwide as first line treatment for uncomplicated malaria, and losing them to resistance would be a disaster for malaria control. Understanding the emergence and spread of antimalarial drug resistance in the context of different scenarios of antimalarial drug use is essential for the development of strategies protecting ACTs. In this study, we review the basic mechanisms of resistance emergence and describe several simple equations that can be used to estimate the probabilities of de novo resistance mutations at three stages of the parasite life cycle: sporozoite, hepatic merozoite and asexual blood stages; we discuss the factors that affect parasite survival in a single host in the context of different levels of antimalarial drug use, immunity and parasitaemia. We show that in the absence of drug effects, and despite very different parasite numbers, the probability of resistance emerging at each stage is very low and similar in all stages (for example per-infection probability of 10,10,10,9 if the per-parasite chance of mutation is 10,10 per asexual division). However, under the selective pressure provided by antimalarial treatment and particularly in the presence of hyperparasitaemia, the probability of resistance emerging in the blood stage of the parasite can be approximately five orders of magnitude higher than in the absence of drugs. Detailed models built upon these basic methods should allow us to assess the relative probabilities of resistance emergence in the different phases of the parasite life cycle. [source] ORIGINAL ARTICLE: Potential for anthropogenic disturbances to influence evolutionary change in the life history of a threatened salmonidEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2008John G. Williams Abstract Although evolutionary change within most species is thought to occur slowly, recent studies have identified cases where evolutionary change has apparently occurred over a few generations. Anthropogenically altered environments appear particularly open to rapid evolutionary change over comparatively short time scales. Here, we consider a Pacific salmon population that may have experienced life-history evolution, in response to habitat alteration, within a few generations. Historically, juvenile fall Chinook salmon (Oncorhynchus tshawytscha) from the Snake River migrated as subyearlings to the ocean. With changed riverine conditions that resulted from hydropower dam construction, some juveniles now migrate as yearlings, but more interestingly, the yearling migration tactic has made a large contribution to adult returns over the last decade. Optimal life-history models suggest that yearling juvenile migrants currently have a higher fitness than subyearling migrants. Although phenotypic plasticity likely accounts for some of the change in migration tactics, we suggest that evolution also plays a significant role. Evolutionary change prompted by anthropogenic alterations to the environment has general implications for the recovery of endangered species. The case study we present herein illustrates the importance of integrating evolutionary considerations into conservation planning for species at risk. [source] ORIGINAL ARTICLE: Big dams and salmon evolution: changes in thermal regimes and their potential evolutionary consequencesEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2008Michael J. Angilletta Jr Abstract Dams designed for hydropower and other purposes alter the environments of many economically important fishes, including Chinook salmon (Oncorhynchus tshawytscha). We estimated that dams on the Rogue River, the Willamette River, the Cowlitz River, and Fall Creek decreased water temperatures during summer and increased water temperatures during fall and winter. These thermal changes undoubtedly impact the behavior, physiology, and life histories of Chinook salmon. For example, relatively high temperatures during the fall and winter should speed growth and development, leading to early emergence of fry. Evolutionary theory provides tools to predict selective pressures and genetic responses caused by this environmental warming. Here, we illustrate this point by conducting a sensitivity analysis of the fitness consequences of thermal changes caused by dams, mediated by the thermal sensitivity of embryonic development. Based on our model, we predict Chinook salmon likely suffered a decrease in mean fitness after the construction of a dam in the Rogue River. Nevertheless, these demographic impacts might have resulted in strong selection for compensatory strategies, such as delayed spawning by adults or slowed development by embryos. Because the thermal effects of dams vary throughout the year, we predict dams impacted late spawners more than early spawners. Similar analyses could shed light on the evolutionary consequences of other environmental perturbations and their interactions. [source] ORIGINAL ARTICLE: Comparison of a point of care device against current laboratory methodology using citrated and EDTA samples for the determination of D-dimers in the exclusion of proximal deep vein thrombosisINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 5 2010P. M. BAKER Summary D-dimer estimation is a routine part of diagnostic algorithms for the exclusion of venous thromboembolism (VTE). We evaluated a point of care device, Biosite Triage (Inverness Medical UK, Cheshire, UK) for the estimation of D-dimers in both samples taken into citrate and EDTA against our routine laboratory D-dimer (Liatest D-dimer, Diagnostica Stago, Reading, UK) performed on the STA-R Evolution. With informed consent, 102 consecutive patients presenting with possible deep vein thrombosis (DVT) were enrolled and D-dimers along with Wells scores and compression ultrasonography (CUS) were recorded. Using the manufacturers' recommended cut offs of 500 ,g/l fibrinogen equivalent units and 400 ,g/l for the Stago and Triage, respectively, sensitivity, specificity, positive and negative predictive values were calculated. These were 1.00, 0.42, 0.17, and 1.00 for the Triage machine using citrate samples, 1.00, 0.32, 0.14, and 1.00 using EDTA samples and 1.00, 0.29, 0.16, and 1.00 for the Stago Liatest assay, respectively. Three patients had significantly higher results for the Stago Liatest D-dimer assay compared with the Biosite Triage device although ultrasound scans were negative. Conclusion: The Biosite Triage D-dimer assay performed on either citrate or EDTA samples is comparable with the Stago Liatest laboratory D-dimer assay when used in conjunction with clinical pretest probability scoring and CUS for the exclusion of DVT. [source] ORIGINAL ARTICLE: Pro-hepcidin and iron metabolism parameters in multi-time blood donorsINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 5 2010J. BOINSKA Summary A high number of blood donations may cause iron depletion. The pathophysiology behind this process may involve hepcidin, a recently discovered peptide that acts by inhibiting iron absorption and promoting iron retention in reticuloendothelial macrophages. The aim of this study was to determine serum pro-hepcidin levels and iron metabolism parameters in multi-time blood donors. The study group consisted of 132 multi-time male blood donors and 25 healthy male volunteers (nondonors). Complete blood cell count and iron status including serum iron, ferritin, soluble transferrin receptor (sTfR), total iron binding capacity (TIBC), unsaturated iron binding capacity (UIBC), erythropoietin and pro-hepcidin (ELISA) were assessed. In blood donors, ferritin level drops markedly in relation to donation frequency (P < 0.001). In contrast, TIBC and UIBC levels increase progressively corresponding to annual donation frequency. Pro-hepcidin concentration increases significantly with the number of donations per year (P = 0.0290). In blood donors having donated blood with the highest frequency per year, pro-hepcidin levels were positively correlated with haemoglobin (R = 0.31, P < 0.05) and negatively with sTfR (R = ,0.31, P < 0.05). Pro-hepcidin levels increase in relation to blood donation frequency per year. Longitudinal studies focusing on changes in serum hepcidin levels are required to address the question whether hepcidin may contribute to iron metabolism disturbances in multi-times blood donors. [source] ORIGINAL ARTICLE: The approach to the mechanism of calcitonin gene-related peptide-inducing inhibition of food intakeJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010J.-Y. Sun Summary The aim of this study was to investigate the anorectic mechanism of calcitonin gene-related peptide (CGRP) in rats. Intraperitoneal injection of CGRP (50 ,g/kg) resulted in decline (p < 0.05) in the food intake of rats at 0.5, 1, 2 and 4 h in comparison with saline control. Compared with saline-treated group, the levels of hypothalamic 3,,5,-cyclic adenosine monophosphate (cAMP) and plasma glucagon were increased (p < 0.05) in CGRP-treated group, but insulin level was decreased (p < 0.05). No significant changes (p > 0.05) in the plasma leptin were observed between two treatment groups. Calcitonin gene-related peptide injection down regulated (p < 0.05) both neuropeptide Y (NPY) and melanin-concentrating hormone (MCH) genes at mRNA levels, but up regulated (p < 0.05) the expression of cholecystokinin (CCK) gene. The correlations analysis showed that food intake was negatively correlated (p < 0.05) with CCK mRNA, cAMP and glucagon levels. Moreover, there existed negative correlations (p < 0.05) between MCH mRNA and glucagon levels, and positive correlations (p < 0.05) between insulin and leptin levels. The results showed that cAMP acting as the second messenger may play a vital role in the anorectic effects of CGRP. Calcitonin gene-related peptide could stimulate anorexigenic neuropeptides (i.e. CCK) and/or inhibit orexigenic neuropeptides (i.e. NPY and MCH) expression, and ultimately suppressed food intake that was functionally coupled to cAMP/PKA pathway activation. [source] ORIGINAL ARTICLE: Application of soybean meal, soy protein concentrate and isolate differing in , -galactosides content to low- and high-fibre diets in growing turkeysJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010Z. Zdu, czyk Summary The aim of this experiment was to investigate the physiological and growth response of young turkeys (up to 8 weeks of age) to dietary replacement of soybean meal (SBM) by soy protein concentrate (PC) or protein isolate (PI). This replacement resulted in a differentiated dietary concentration of , -galactosides of over 2.5% in the SBM diet, approximately 2% with a mixture SBM and PC, 1% with a PC diet and 0.1% with a PI diet. Each treatment was applied in two ways: with lower (3.5%) or higher (5.3%) dietary crude fibre content, made by supplementation with soybean hulls. The highest and lowest body weight of turkeys was recorded both after the first and second 4-week half of the study in the PC and PI-type diets respectively. A gradual withdrawal of , -galactosides from a diet was accompanied by a decline in ileal tissue mass, ileal viscosity and activity of endogenous maltase (the latter was found to be significant at 4 weeks of age). At the same time, two-way anova revealed that an elevated level of crude fibre (HF treatment) caused an increase in ileal tissue mass (p < 0.05 after 4 weeks of feeding) as well as a decrease in activity level of intestinal sucrase and maltase. The presence of raffinose family oligosaccharides in a diet, in contrast to dietary crude fibre level, significantly affected the caecal metabolism. The rate of bacterial production of short-chain fatty acids in the caeca was distinctly diminished by dietary withdrawal of , -galactosides. In conclusion, the soy protein concentrate, in contrast to the protein isolate preparation, exerted positive effects on the turkeys' growth and gastrointestinal tract physiology and should be considered as an effective SBM substitute. [source] ORIGINAL ARTICLE: Ileal endogenous amino acid flow of broiler chickens under high ambient temperatureJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010A. F. Soleimani Summary High environmental temperature has detrimental effects on the gastrointestinal tract of poultry. An experiment was conducted to determine the effect of acute heat stress on endogenous amino acid (EAA) flow in broiler chickens. A total of 90, day-old broiler chicks were housed in battery cages in an environmentally controlled chamber. Chicks were fed a nitrogen-free diet on day 42 following either no heat exposure (no-heat) or 2 weeks exposure to 35 ± 1 °C for 3 h from days 28 to 42 (2-week heat) or 1 week exposure to 35 ± 1 °C for 3 h from days 35 to 42 (1 week heat). The most abundant amino acid in the ileal flow was glutamic acid, followed by aspartic acid, serine and threonine in non-heat stressed group. The EAA flow in 1-week heat and 2-week heat birds were significantly (p < 0.05) higher than those under no heat exposure (14682, 11161 and 9597 mg/kg of dry matter intake respectively). Moreover, the EAA flow of 2-week heat group was less than 1-week heat group by approximately 36%. These observations suggest that the effect of heat stress on EAA flow is mostly quantitative; however, heat stress may also alter the content of EAA flow qualitatively. [source] ORIGINAL ARTICLE: Description of development of rumen ecosystem by PCR assay in milk-fed, weaned and finished lambs in an intensive fattening systemJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010A. Belanche Summary This study examined the reticulo-rumen characteristics of the microbial community and its fermentative characteristics in milk-fed, at weaning and finished lambs in a conventional fattening system. Five lambs were assigned to each of three groups: milk-fed lambs slaughtered at 30 days (T30), weaned lambs slaughtered at 45 days (T45) and ,finished lambs' slaughtered at 90 days (T90). At slaughter, rumen size, fermentation parameters (pH, volatile fatty acids and microbial enzyme activity) and protozoal counts were recorded. Quantitative PCR was used to quantify the genes encoding 16S and 18S ribosomal DNA of the rumen bacterial and protozoal populations, respectively, and the sequential colonization of the rumen by cellulolytic (Ruminococcus albus, Ruminococcus flavefaciens) and amylolytic (Prevotella ruminicola, Streptococcus bovis) bacteria, and protozoa (Entodinium sp.). Denaturing gradient gel electrophoresis was used to study the development of rumen microbiota biodiversity. Intake of solid food before weaning caused a significant increase in rumen weight (p < 0.0001) and bacterial DNA (p < 0.05) and volatile fatty acid analysis concentration (p < 0.01), whereas pH declined. In milk-fed lambs, cellulolytic bacteria were evident after 30 days. Thereafter, in the 45-day and 90-day groups, the proportions of R. flavefaciens decreased and R. albus increased. Amylolytic bacteria were present in milk-fed lambs; the proportion of P. ruminicola increased in fattening lambs and S. bovis was the least abundant species. Protozoal concentrations were irregular; milk-fed lambs had a significant number of protozoa species from Entodinium and subfamily Isotrichiidae, but they disappeared at weaning. Lamb rumen were refaunated in some individuals at 90 days (Entodinium and subfamily Diplodiniinae spp.), although individual concentrations were variable. [source] ORIGINAL ARTICLE: Echinacea purpurea and Allium sativum as immunostimulants in fish culture using Nile tilapia (Oreochromis niloticus)JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010S. M. Aly Summary The study was conducted to evaluate the efficiency of echnicacea (E) and garlic (G) supplemented diets as immunostimulant for tilapia (Oreochromis niloticus). Seven treatments were designed including a control (C). Fish were fed on 35% protein diet at a rate of 3% body weight per day. Echinacea (1.0 ppt) and garlic (3%) were incorporated in the feed, which was administered for periods of 1, 2 and 3 months (summer season), followed by basal diet for 4 more months (winter season). Neutrophil adherence and haematocrit values increased in both supplemented groups with prolonging period of application. The neutrophils adherence was significantly increased in all treatments except group administered echinacea for 1 month. The lymphocytic counts were significantly (p < 0.004) elevated that resulted in a significant increase in the total leucocytic count in groups administered echinacea for 1 and 2 months when compared with the control and/or other treatments. The gain in the body weight and specific growth rate was significantly increased in all supplemented groups (p < 0.004) during summer, but remained without any significant increase after winter. The survival rate was significantly high (>85%) in all the supplemented groups. The percentage of protection, after challenge infection using pathogenic Aeromonas hydrophila was the highest in groups supplemented with echinacea and garlic for 3 months after summer and winter seasons. It could be concluded that echinacea and garlic improve the gain in body weight, survival rate and resistance against challenge infection. Both compounds showed extended effects after withdrawal and improved resistance to cold stress during the winter season. However, a full commercial cost benefit analysis is necessary before recommending their application in aquaculture. [source] ORIGINAL ARTICLE: Effects of dietary supplementation of synbiotics and phytobiotics on performance, caecal coliform population and some oxidant/antioxidant parameters of broilersJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010Z. Erdo Summary The current study was conducted to evaluate the effects of dietary supplementation of synbiotics and phytobiotics on performance, small intestine weight, pH and caecal coliform counts of broilers. The influences of synbiotics and phytobiotics on oxidant/antioxidant status in the blood of broilers were also assessed. A total of 200 broiler chicks were randomly allotted to four dietary treatments, either fed a basal diet or the same diet supplemented with 1 g/kg synbiotic, 1 g/kg phytobiotic or 1 g/kg synbiotic plus 1 g/kg phytobiotic. The diet supplemented with both synbiotic and phytobiotic had no effect on body weight, body weight gain, feed intake and feed efficiency of broilers at the end of the study (p > 0.05). Neither small intestine weight nor pH was affected by any of the treatments. Supplementation of both synbiotic and phytobiotic to diet decreased the caecal coliform count (p < 0.01). Addition of synbiotics and phytobiotics in combination significantly increased plasma malondialdehyde (MDA) levels (p , 0.05), whereasphytobiotic addition alone showed only a slight increase. Similarly, elevated nitric oxide (NO) level was recorded in the synbiotic- and phytobiotic-fed group and in the phytobiotic-fed group (p , 0.001). Superoxide dismutase (SOD) activities did not differ between the groups. In conclusion, dietary supplementation of synbiotic and phytobiotic improved the gut health by decreasing the caecal total coliform count, but growth performance was not affected by the supplementations. Further investigations are needed to determine the effects of phytobiotics on oxidative/antioxidative metabolism as regards their compositional analysis. [source] ORIGINAL ARTICLE: Brain and hypophyseal acetylcholinesterase activity of pubertal boars fed dietary fumonisin B1JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010F. A. Gbore Summary The effects of dietary fumonisin B1 (FB1) on regional brain and hypophyseal activities of AChE (EC 3117), the enzyme which catalyses the hydrolysis of acetylcholine, were studied using 24 male Large White weanling pigs divided into four groups. Each group received one of the four diets containing 0.2, 5.0, 10.0 and 15.0 mg FB1/kg in a 6-month feeding trial. All animals were slaughtered at the end of the feeding trial; the brains and the hypophyses obtained were carefully dissected out. Significant (p < 0.05) influence of dietary FB1 on regional brain and hypophyseal AChE activities were observed. The AChE activities in the pons, amygdala, hypothalamus and the medulla oblongata declined significantly (p < 0.05) with increased dietary FB1 concentrations. The findings of this study suggest that diets containing 5.0 mg FB1/kg and above significantly (p < 0.05) altered regional brain and hypophyseal AChE activities in the animals. Dietary exposure to FB1 at a concentration of approximately 5.0 mg/kg or more for a 6-month period is a potential health risk that may induce adverse physiological response resulting from altered brain neurochemistry in growing pigs. [source] ORIGINAL ARTICLE: Intestinal villus histological alterations in broilers fed dietary dried fermented gingerJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010T. Incharoen Summary To evaluate the effect of dietary dried fermented ginger (DFG) on intestinal villous histological alteration and growth performance, 64 Marshall Chunky male broilers were divided into four groups, each with four replicates of four chickens. Birds were fed the basal commercial mash diet supplemented with DFG at 0 (control), 5, 10 and 20 g/kg for 42 days. With increasing dietary DFG levels, feed intake tended to decrease and significantly decreased in the 20 g/kg DFG group (p < 0.05). Weight gain was higher in all the DFG groups, with the highest in the 10 g/kg DFG group (p < 0.05), resulting in an improved feed efficiency in all the DFG groups. Intestinal villus height, villus area, cell area and cell mitosis in all the intestinal segments were higher in all the DFG groups than in the control group. Protuberated cells and cell clusters were found in all the DFG groups, suggesting that the intestinal villi and cells might be hypertrophied. The present results indicate that dietary DFG can be used as a natural feed additive to induce broiler growth performance as a result of stimulation of morphological maturation and in consequence intestinal function. [source] ORIGINAL ARTICLE: Effect of Lactobacillus fermentum and Enterococcus faecium strains on internal milieu, antioxidant status and body weight of broiler chickensJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010M. Capcarova Summary The aim of the present study was to evaluate the functional efficiency of two probiotic strains Lactobacillus fermentum CCM 7158 and Enterococcus faecium M 74 given to the drinking water on internal milieu, antioxidant status and body weight of broiler chickens. The experiment was conducted on hybrid Hybro (n = 180). The feeding period lasted 42 days. Experimental chickens of E1 group received a probiotic preparation in drinking water with concentration of 1 × 109 colony forming units (CFU) of L. fermentum CCM 7158 in 1 g of nutrient medium and experimental chickens of E2 group concentration of 2 × 109 CFU of E. faecium M 74 in 1 g of nutrient medium. The control group of animals received water without any additives. Triglycerides content in serum mainly with L. fermentum strain against the control group was decreased. Calcium content in both experimental groups and significantly in E. faecium group was increased. Antioxidant status in both probiotic groups was significantly increased. The content of bilirubin in group with E. faecium M 74 was significantly increased. In conclusion, addition of a microbial feed additive (L. fermentum and E. faecium) increased serum calcium and iron level, decreased triglycerides content in blood and slightly increased body weight of broiler chickens. [source] ORIGINAL ARTICLE: Coalescent analyses support multiple mainland-to-island dispersals in the evolution of Malagasy Triaenops bats (Chiroptera: Hipposideridae)JOURNAL OF BIOGEOGRAPHY, Issue 6 2008Amy L. Russell Abstract Aim, We investigate the directionality of mainland-to-island dispersals, focusing on a case study of an African-Malagasy bat genus, Triaenops (Hipposideridae). Taxa include T. persicus from east Africa and three Triaenops species from Madagascar (T. auritus, T. furculus, and T. rufus). The evolution of this bat family considerably post-dated the tectonic division of Madagascar from Africa, excluding vicariance as a viable hypothesis. Therefore, we consider three biogeographical scenarios to explain these species' current ranges: (A) a single dispersal from Africa to Madagascar with subsequent speciation of the Malagasy species; (B) multiple, unidirectional dispersals from Africa to Madagascar resulting in multiple, independent Malagasy lineages; or (C) early dispersal of a proto-species from Africa to Madagascar, with later back-dispersal of a descendant Malagasy taxon to Africa. Location, East Africa, Madagascar, and the Mozambique Channel. Methods, We compare the utility of phylogenetic and coalescent methodologies to address the question of directionality in a mainland-to-island dispersal event for recently diverged taxa. We also emphasize the application of biologically explicit demographic systems, such as the non-equilibrium isolation-with-migration model. Here, these methods are applied to a four-species haploid genetic data set, with simulation analyses being applied to validate this approach. Results, Coalescent simulations favour scenario B: multiple, unidirectional dispersals from Africa to Madagascar resulting in multiple, independent Malagasy bat lineages. From coalescent dating, we estimate that the genus Triaenops was still a single taxon approximately 2.25 Ma. The most recent Africa to Madagascar dispersal occurred much more recently (c. 660 ka), and led to the formation of the extant Malagasy species, T. rufus. Main conclusions, Haploid genetic data from four species of Triaenops are statistically most consistent with multiple, unidirectional dispersals from mainland Africa to Madagascar during the late Pleistocene. [source] ORIGINAL ARTICLE: Cycads in the insular South-west Pacific: dispersal or vicariance?JOURNAL OF BIOGEOGRAPHY, Issue 6 2008Gunnar Keppel Abstract Aim, Cycads constitute an ancient plant group that is generally believed to disperse poorly. However, one group of cycads (subsection Rumphiae) is thought to have dispersed relatively recently from a Malesian source area westwards to East Africa and eastwards into the Pacific, using a floatation-facilitating layer in their seeds. We use morphological and allozyme characters to investigate the relationships among the species within this group and to deduce whether the wide distribution was achieved by recent dispersal (as evidenced by high genetic similarity) or more distant vicariance events (high genetic differentiation). Location, We examined specimens collected throughout the range of subsection Rumphiae, from East Africa through Southeast Asia to Tonga in the South-west Pacific. Methods, We investigated relationships within subsection Rumphiae of the genus Cycas by analysing 18 variable (11 informative) morphological characters and 22 allozyme loci for seven of the 10 species currently assigned to this taxon. Results, Distinctive morphological characters are few and fail to resolve relationships within the group. Allozyme data show that species within this subsection are closely related and suggest that there are two groups within the subsection, one comprising Cycas thouarsii (East Africa) and C. edentata (the Philippines), and the other the remaining species (from Malesia and the Pacific). The Australian species C. silvestris is sister to subsection Rumphiae in the morphological analysis but is closely allied to C. rumphii (nested within the subsection) in the allozyme analysis, suggesting that Rumphiae may be paraphyletic and that characters thought to be taxonomically important may need to be re-evaluated. Main conclusions, Cycads within subsection Rumphiae are closely related, and the wide distribution of this group was probably achieved through relatively recent oceanic dispersal events. Separate events probably account for the dispersal of these cycads into the Pacific and to Africa. The origin and distribution of C. silvestris (Australia) could be explained by a dispersal event from New Guinea or may have resulted from a former land connection between Australia and New Guinea. [source] ORIGINAL ARTICLE: The biogeography of avian extinctions on oceanic islandsJOURNAL OF BIOGEOGRAPHY, Issue 6 2008Tim J. Karels Abstract Aim, To test the influences of island area, island isolation, and human-introduced mammalian predators on avian extinctions that have occurred on oceanic islands worldwide. Location, The oceanic islands of the world. Methods, We augmented and re-examined an existing data set for 218 oceanic islands by means of causal modelling using path analysis (a form of structural equation modelling) and a null model. Results, The number of extinctions was not a simple function of the number of bird species on the various islands. Whereas introduced mammalian predators had an influence on the number of extinctions, island area (via indirect influences) and isolation (via direct influences) were equally or more important. Main conclusions, The multiple influences of physical and biotic factors on past extinctions can be revealed through modelling the causal influences of physical attributes of islands on biological characteristics, and the causal influences of both physical and biological characteristics on extinctions. [source] ORIGINAL ARTICLE: Extinction of the autochthonous small mammals of Mallorca (Gymnesic Islands, Western Mediterranean) and its ecological consequencesJOURNAL OF BIOGEOGRAPHY, Issue 6 2008Pere Bover Abstract Aim, To investigate the chronology, causes and consequences of the extinction of the autochthonous Pleistocene small mammals of Mallorca. Location, Mallorca (Gymnesic Islands, Balearics, Western Mediterranean). Methods, We have obtained the first direct 14C ages from the bone collagen of selected samples of two extinct endemic small mammals from Mallorca: the Balearic dormouse, Eliomys morpheus (Rodentia: Myoxidae) and the Balearic shrew, Asoriculus hidalgoi (Soricomorpha: Soricidae). We also present evidence for the absence of both endemics from the earliest Mallorcan archaeological sites and for the introduction of the garden dormouse, Eliomys quercinus, and the wood mouse, Apodemus sylvaticus. Combined information from direct dating of bone collagen of E. quercinus and A. sylvaticus and from cultural associations provides an adequate framework to establish the chronology of the faunal change and to compare it with the chronological information available on climatic change and the first arrival of humans on the islands. Results, The chronological record includes the latest evidence available for the survival of endemic species and the earliest introduction of small mammals into Mallorca. We present ,uncertainty periods for extinction' (UPEs) of both endemic mammals based on the chronology of their last occurrence and on the inferred timing of their extinction (restricted UPEs). Main conclusions, Possible causes for the extinction of autochthonous small mammals on Mallorca are discussed. Once we have discarded climatic causes, predation by invasive species, competition with newcomers and habitat deterioration, the introduction of diseases emerges as the most reasonable explanation for these extinctions. Based on the identification of changes in keystone species in Mallorcan ecosystems, we propose a tentative schedule of key ecological changes that have taken place over the past 5 millennia. [source] ORIGINAL ARTICLE: Freshwater paths across the ocean: molecular phylogeny of the frog Ptychadena newtoni gives insights into amphibian colonization of oceanic islandsJOURNAL OF BIOGEOGRAPHY, Issue 1 2007G. John Measey Abstract Aim, Amphibians are a model group for studies of the biogeographical origins of salt-intolerant taxa on oceanic islands. We used the Gulf of Guinea islands to explore the biogeographical origins of island endemism of one species of frog, and used this to gain insights into potential colonization mechanisms. Location, São Tomé and Príncipe, two of the four major islands in the Gulf of Guinea, West Africa, are truly oceanic and have an exceptionally high biodiversity. Methods, Mitochondrial DNA is used to test the endemic status of a frog from São Tomé and compare it with congeneric taxa from tropical Africa. Existing data on surface currents, surface salinity, atmospheric circulation and bird migration in the Gulf of Guinea are summarized to address hypotheses concerning colonization mechanisms. Results, The endemic status of Ptychadena newtoni (Bocage) is supported here by mitochondrial DNA sequences, and analysis of this and other molecular data indicates that an East African species close to Ptychadena mascareniensis (Duméril and Bibron) is its nearest relative. We refute the possibility that this population was anthropogenically introduced, in favour of a natural dispersal mechanism. Main conclusions, With six endemic frogs and one caecilian, the Gulf of Guinea islands harbour a diverse amphibian fauna. Five of these species appear to have their closest relatives in East Africa. Insufficient evidence exists for transportation by storms, birds or rafts alone. However, we propose a synergy of rafting, favourable surface currents and a reduction in salinity of surface waters. Catastrophic events, or wet periods in climatic history, could allow freshwater paths to open far enough to enable continental flora and fauna to reach these and other isolated oceanic islands. [source] ORIGINAL ARTICLE: Predicting species distributions from small numbers of occurrence records: a test case using cryptic geckos in MadagascarJOURNAL OF BIOGEOGRAPHY, Issue 1 2007Richard G. Pearson Abstract Aim, Techniques that predict species potential distributions by combining observed occurrence records with environmental variables show much potential for application across a range of biogeographical analyses. Some of the most promising applications relate to species for which occurrence records are scarce, due to cryptic habits, locally restricted distributions or low sampling effort. However, the minimum sample sizes required to yield useful predictions remain difficult to determine. Here we developed and tested a novel jackknife validation approach to assess the ability to predict species occurrence when fewer than 25 occurrence records are available. Location, Madagascar. Methods, Models were developed and evaluated for 13 species of secretive leaf-tailed geckos (Uroplatus spp.) that are endemic to Madagascar, for which available sample sizes range from 4 to 23 occurrence localities (at 1 km2 grid resolution). Predictions were based on 20 environmental data layers and were generated using two modelling approaches: a method based on the principle of maximum entropy (Maxent) and a genetic algorithm (GARP). Results, We found high success rates and statistical significance in jackknife tests with sample sizes as low as five when the Maxent model was applied. Results for GARP at very low sample sizes (less than c. 10) were less good. When sample sizes were experimentally reduced for those species with the most records, variability among predictions using different combinations of localities demonstrated that models were greatly influenced by exactly which observations were included. Main conclusions, We emphasize that models developed using this approach with small sample sizes should be interpreted as identifying regions that have similar environmental conditions to where the species is known to occur, and not as predicting actual limits to the range of a species. The jackknife validation approach proposed here enables assessment of the predictive ability of models built using very small sample sizes, although use of this test with larger sample sizes may lead to overoptimistic estimates of predictive power. Our analyses demonstrate that geographical predictions developed from small numbers of occurrence records may be of great value, for example in targeting field surveys to accelerate the discovery of unknown populations and species. [source] ORIGINAL ARTICLE: Towards an understanding of the Holocene distribution of Fagus sylvatica L.JOURNAL OF BIOGEOGRAPHY, Issue 1 2007Thomas Giesecke Abstract Aim, Understanding the driving forces and mechanisms of changes in past plant distribution and abundance will help assess the biological consequences of future climate change scenarios. The aim of this paper is to investigate whether modelled patterns of climate parameters 6000 years ago can account for the European distribution of Fagus sylvatica at that time. Consideration is also given to the role of non-climatic parameters as driving forces of the Holocene spread and population expansion of F. sylvatica. Location, Europe. Methods, European distributions were simulated using a physiologically-based bioclimatic model (STASH) driven by three different atmospheric general circulation model (AGCM) outputs for 6000 years ago. Results, The three simulations generally showed F. sylvatica to have potentially been as widespread 6000 years ago as it is today, which gives a profound mismatch with pollen-based reconstructions of the F. sylvatica distribution at that time. The results indicate that drier conditions during the growing season 6000 years ago could have caused a restriction of the range in the south. Poorer growth conditions with consequently reduced competitive ability were modelled for large parts of France. Main conclusions, Consideration of the entire European range of F. sylvatica showed that no single driving force could account for the observed distributional limits 6000 years ago, or the pattern of spread during the Holocene. Climatic factors, particularly drought during the growing season, are the likely major determinants of the potential range. Climatic factors are regionally moderated by competition, disturbance effects and the intrinsically slow rate of population increase of F. sylvatica. Dynamic vegetation modelling is needed to account for potentially important competitive interactions and their relationship with changing climate. We identify uncertainties in the climate and pollen data, as well as the bioclimatic model, which suggest that the current study does not identify whether or not climate determined the distribution of F. sylvatica 6000 years ago. Pollen data are better suited for comparison with relative abundance gradients rather than absolute distributional limits. These uncertainties from a study of the past, where we have information about plant distribution and abundance, argue for extreme caution in making forecasts for the future using equilibrium models. [source] ORIGINAL ARTICLE: Solubilization of vorinostat by cyclodextrinsJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2010Y. Y. Cai BSc Summary Background:, Vorinostat (suberoylanilide hydroxamic acid) is the first histone deacetylase inhibitor approved by US FDA for use in oncology. However, as a hydrophobic acid, its limited aqueous solubility poses a problem for parenteral delivery. Such limited solubility may also affect its oral bioavailability. Objective:, The aim of this study was to evaluate whether cyclodextrins (CDs), common excipients used in pharmaceutical industry, could increase the aqueous solubility of vorinostat. Methods:, The actual aqueous solubility of vorinostat was investigated by phase-solubility method. Molecular simulation was employed to predict the interaction energy and preferred orientation of vorinostat in CD cavities. Results:, Phase-solubility studies indicated that the solubility of vorinostat (7·24 × 10,1 mm) was substantially increased when complexed with various CDs, in the following order: randomly methylated-,-cyclodextrin (RM-,-CD) > hydroxypropyl-,-cyclodextrin (HP-,-CD) > ,-cyclodextrin > hydroxypropyl-,-cyclodextrin > Hydroxypropyl-,-cyclodextrin > ,-cyclodextrin. RM-,-CD 300 mm increased vorinostat solubility to 70·8 mm, almost two orders of magnitude higher than the baseline solubility. Such findings were in good agreement with the results obtained from molecular simulation. Conclusion:, CDs, particularly RM-,-CD and HP-,-CD, increased vorinostat's solubility. Future studies could be focused on the application of HP-,-CD in parenteral delivery of vorinostat or using RM-,-CD as an oral absorption enhancer. Molecular simulation appeared to be a useful tool for the selection of appropriate CD as excipient for drug delivery. [source] ORIGINAL ARTICLE: Investigation of the prediction accuracy of vancomycin concentrations determined by patient-specific parameters as estimated by Bayesian analysisJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2010Y. Hiraki BSc Summary Background/Objective:, There have been many studies of therapeutic drug monitoring (TDM) of vancomycin (VCM) based on Bayesian analysis, but there have been no reports of the accuracy of prediction based on Bayesian-estimated patient-specific parameters. This study was conducted to compare the accuracy of prediction based on the population pharmacokinetic (PPK) method and Bayesian-estimated parameters. Method:, The subjects were 22 patients who were treated with VCM for MRSA infection and whose blood was sampled twice or more during the administration period. The concentrations between the blood samples were predicted based on the concentrations in the first blood samples based on the PPK method using mean parameters for the Japanese population and Bayesian-estimated patient-specific pharmacokinetic parameters. The mean prediction error (ME), mean absolute error (MAE) and root mean squared error (RMSE) were compared to examine the accuracy of prediction based on Bayesian-estimated patient-specific parameters. Results and discussion:, The mean measured VCM concentration was 10·43 ± 5·19 ,g/mL, whereas the mean concentration predicted based on the PPK method was 8·52 ± 4·34 ,g/mL, with an ME of ,1·91, MAE of 2·93 and RMSE of 3·21. The mean concentration predicted based on patient-specific parameters was 9·62 ± 4·95 ,g/mL with ME of ,0·81, MAE of 1·38 and RMSE of 1·74. The ME and MAE for the concentrations predicted using patient-specific parameters were smaller compared with those predicted using the PPK method (P = 0·0471 and 0·0003, respectively), indicating superior prediction with a significant difference between approaches. Conclusion:, Prediction using Bayesian estimates of patient-specific parameters was better than by the PPK method. However, when using patient-specific parameters it is still necessary to fully understand the clinical status of the patient and frequently determine VCM concentrations. [source] ORIGINAL ARTICLE: Prevalence and correlates of metabolic syndrome based on a harmonious definition among adults in the US,JOURNAL OF DIABETES, Issue 3 2010Earl S. FORD Abstract Background:, Recently, a Joint Scientific Statement bridged differences between previous definitions of metabolic syndrome. Our objective was to estimate the prevalence of metabolic syndrome in a representative sample of US adults and to examine its correlates. Methods:, We analyzed data for up to 3461 participants aged ,20 years of the 2003,2006 National Health and Nutrition Examination Survey. Results:, Using waist circumference thresholds of ,102 cm for men and ,88 cm for women, the age-adjusted prevalence of metabolic syndrome was 34.3% among all adults, 36.1% among men, and 32.4% among women. Using racial- or ethnic-specific International Diabetes Federation criteria for waist circumference, the age-adjusted prevalence of metabolic syndrome was 38.5% for all participants, 41.9% for men, and 35.0% for women. Prevalence increased with age, peaking among those aged 60,69 years. Prevalence was lower among African American men than White or Mexican American men, and lower among White women than among African American or Mexican American women. In a multivariate regression model, significant independent associations were noted for age (positive), gender (men higher than women), race or ethnicity (African Americans and participants of another race lower than Whites), educational status (inverse), hypercholesterolemia (positive), concentrations of C-reactive protein (positive), leisure time physical activity (inverse), microalbuminuria (positive), and hyperinsulinemia (positive). Additional adjustment for body mass index weakened many of the associations, with educational status and microalbuminuria no longer significant contributors to the model. Conclusion:, Metabolic syndrome continues to be highly prevalent among adults in the US. [source] ORIGINAL ARTICLE: Many patients with Type 1 diabetes estimate their prandial insulin need inappropriatelyJOURNAL OF DIABETES, Issue 3 2010Aila J. AHOLA Abstract Background:, Many factors contribute to the need for prandial insulin in Type 1 diabetes. However, patients' success in achieving normal postprandial glucose concentration is understudied. The aim of the present study was to determine how often patients with Type 1 diabetes achieve normal postprandial glucose concentrations and to evaluate factors associated with postprandial hypo- and hyperglycemia. Methods:, Data on food intake, physical activity, insulin administration, and blood glucose concentration were collected using a self-administered questionnaire from 331 patients with Type 1 diabetes (43% men; mean age 49 ± 12 years; mean diabetes duration 32 ± 13 years). Of these, 179 provided data on blood glucose concentrations measured 110,150 min postprandially. One such meal per patient was randomized for analyses. Results:, Hypoglycemia (<4.0 mmol/L), normoglycemia (4.0,7.9 mmol/L), and hyperglycemia (,8.0 mmol/L) were observed after 23%, 36%, and 41% of meals, respectively. The three postprandial glycemia groups did not differ with respect to the meal composition or the timing of the postprandial blood glucose measurement. In women, postprandial hyperglycemia was associated with shorter diabetes duration and higher preprandial blood glucose concentration, whereas postprandial hypoglycemia was associated with higher physical activity. No single factor explained the postprandial glycemic state in men. Conclusions:, A total of 64% of patients estimated their prandial insulin need inappropriately, suggesting that estimation of the optimal prandial insulin dose is not easy, even after a long duration of diabetes. [source] ORIGINAL ARTICLE: Lessons from families and communities about interpersonal violence, victimization, and seeking helpJOURNAL OF FORENSIC NURSING, Issue 3 2010Angela Frederick Amar PhD Abstract Despite significant incidence and physical and mental health consequences, most college-age women do not tell anyone about experiences of interpersonal violence. Limited research explores the sociocultural context of seeking help related to violence in young women. The overall purpose of this research was to understand socially and culturally relevant factors associated with violence help seeking in college women. Eight focus groups were held with 64 participants. Narrative analysis was the primary method of analysis. Four qualitative categories emerged from the data: "Learning from one's mother"; "We're strong women; we fight"; "We didn't talk about it"; and "Where I'm from." Findings suggest that help seeking is influenced by the messages from and experiences of mothers and extended family members. An understanding of familial and cultural determinants of help seeking is essential for relevant and effective prevention efforts. [source] ORIGINAL ARTICLE: Comparison by crime type of juvenile delinquents on pornography exposure: The absence of relationships between exposure to pornography and sexual offense characteristics1JOURNAL OF FORENSIC NURSING, Issue 3 2010David L. Burton MSW Abstract Previous literature on pornography indicates that pornography use for men at risk for aggression may result in sexually aggressive behavior, but very little research has been reported on juvenile sexual abusers' exposure to pornography. The current study compared pornography exposure between male adolescent sexual abusers (n= 283) and male nonsexually offending delinquent youth (n= 170). Sexual abusers reported more pre- and post-10 (years of age) exposure to pornography than nonsexual abusers. Yet, for the sexual abusers, exposure is not correlated to the age at which the abusers started abusing, to their reported number of victims, or to sexual offense severity. The pre-10 exposure subscale was not related to the number of children the group sexually abused, and the forceful exposure subscale was not correlated with either arousal to rape or degree of force used by the youth. Finally, exposure was significantly correlated with all of the nonsexual crime scores in the study. Implications for forensic nursing are discussed. [source] | ||||||||||||||||