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Terms modified by O. Selected AbstractsA novel exocrine structure of the bicellular unit type in the thorax of termitesACTA ZOOLOGICA, Issue 2 2010Teresa Telles Gonçalves Abstract Gonçalves, T. T., DeSouza, O. and Billen, J. 2010. A novel exocrine structure of the bicellular unit type in the thorax of termites , Acta Zoologica (Stockholm) 91: 193,198 Studying the thorax of some Termitidae species, we found two pairs of hitherto unknown lateral glands in the mesothorax and metathorax of both workers and soldiers. The glands consist of distinct clusters of class 3 secretory cells accompanied by their duct cells, located in the upper lateral portion of the thoracic wall. Ultrastructural observations reveal numerous mitochondria, a well-developed Golgi apparatus and vesicular smooth endoplasmic reticulum, indicating a cytoplasm with intensive metabolic activity. The gland is reported to occur in Microcerotermes strunckii, Cornitermes cumulans and Nasutitermes minor, three species comprising an interesting morpho-behavioural gradient, respectively, from only mechanical, through mechanical,chemical, to only chemical defence systems. The extent of such a gradient allows speculations that this gland would be related to the general needs of termites, rather than to some specificities of a single group. We warn, however, that complementary studies are needed, before any conclusions can be drawn. [source] The evolution of the protonephridial terminal organ across Rotifera with particular emphasis on Dicranophorus forcipatus, Encentrum mucronatum and Erignatha clastopis (Rotifera: Dicranophoridae)ACTA ZOOLOGICA, Issue 2 2010Ole Riemann Abstract Riemann, O. and Ahlrichs, W.H. 2009. The evolution of the protonephridial terminal organ across Rotifera with particular emphasis on Dicranophorus forcipatus, Encentrum mucronatum and Erignatha clastopis (Rotifera: Dicranophoridae). ,Acta Zoologica (Stockholm) 91: 199,211 We report on the ultrastructure of the protonephridial terminal organ in three species of dicranophorid rotifers (Dicranophorus forcipatus, Encentrum mucronatum and Erignatha clastopis). Differences between the three species relate to shape and size, the morphology of the filter region and the number of microvilli and cilia inside the terminal organ. A comparison across Rotifera indicates that the terminal organs in D. forcipatus display a number of plesiomorphic characters, but are modified in E. mucronatum and Er. clastopis. This is in accordance with the results of phylogenetic analyses suggesting a basal position of D. forcipatus compared with the more derived species E. mucronatum and Er. clastopis. Moreover, we survey available data on the terminal organ in Rotifera and discuss its evolutionary transformations. The protonephridial terminal organ in the common ancestor of Rotifera consisted of a cytoplasmic cylinder with cilia united into a vibratile flame and a single circle of circumciliary microvilli. Depending on the topology on which characters are optimized, the site of ultrafiltration was formed by longitudinal cytoplasmic columns spanned by a fine filter diaphragm or by pores in the wall of the terminal organ. In several taxa of Rotifera, the terminal organ , probably independently , lost its circumciliary microvilli. [source] Association of mast cells with tumor angiogenesis in esophageal squamous cell carcinomaDISEASES OF THE ESOPHAGUS, Issue 2 2001M. Tomita The association of mast cells with tumor angiogenesis was investigated in patients with esophageal squamous cell carcinoma. Surgical specimens from 48 patients with esophageal squamous cell carcinoma were studied. Mast cells in tumor sections were stained with Alcian blue and safranin O. The number of mast cells was counted under light microscopy and the average count recorded. To highlight the microvessels, endothelial cells were stained with anti-human factor VIII antibody. Microvessel density was also counted. We found a significant correlation between mast cell count and microvessel density in patients with esophageal squamous cell carcinoma. Double staining of the microvessels revealed highly angiogenic areas densely populated with mast cells. There appears to be a direct correlation between the number of mast cells and tumor angiogenesis in patients with esophageal squamous cell carcinoma. [source] Subterranean species of the ant genus Crematogaster in Asia (Hymenoptera: Formicidae)ENTOMOLOGICAL SCIENCE, Issue 3 2010Shingo HOSOISHI Abstract Three Crematogaster ant species, C. (Orthocrema) javanica Menozzi, C. (O.) myops Forel and C. (O.) masukoi sp. nov., share reduced compound eyes which characterizes them among Asian species of the subgenus Orthocrema. The new species is described based on material from Borneo. It can be distinguished from C. javanica and C. myops by its smooth surface of clypeus and acutely produced subpetiolar process. Reduced compound eyes and yellowish body suggest that these three species are subterranean. [source] Reply to comment on ,Kisi O. 2007.HYDROLOGICAL PROCESSES, Issue 14 2008Evapotranspiration modelling from climatic data using a neural computing technique. No abstract is available for this article. [source] Mining an Ostrinia nubilalis midgut expressed sequence tag (EST) library for candidate genes and single nucleotide polymorphisms (SNPs)INSECT MOLECULAR BIOLOGY, Issue 6 2008B. S. Coates Abstract Genes expressed in lepidopteran midgut tissues are involved in digestion and Bacillus thuringiensis (Bt) toxin resistance traits. Five hundred and thirty five unique transcripts were annotated from 1745 high quality O. nubilalis larval midgut expressed sequence tags (ESTs). Full-length cDNA sequence of 12 putative serine proteinase genes and 3 partial O. nubilalis aminopeptidase N protein genes, apn1, apn3, and apn4, were obtained, and genes may have roles in plant feeding and Bt toxin resistance traits of Ostrinia larvae. The EST library was not normalized and insert frequencies reflect transcript levels under the initial treatment conditions and redundancy of inserts from highly expressed transcripts allowed prediction of putative single nucleotide polymorphisms (SNPs). Ten di-, tri- or tetranucleotide repeat unit microsatellite loci were identified, and minisatellite repeats were observed within the C-termini of two encoded serine proteinases. Molecular markers showed polymorphism at 28 SNP loci and one microsatellite locus, and Mendelian inheritance indicated that markers were applicable to genome mapping applications. This O. nubilalis larval midgut EST collection is a resource for gene discovery, expression information, and allelic variation for use in genetic marker development. [source] Bone adaptation to load: microdamage as a stimulus for bone remodellingJOURNAL OF ANATOMY, Issue 6 2002T. C. Lee Abstract Mechanical loading in the proximal radius was increased by ulnar osteotomy (Group O), altered by Steinmann pinning (Group P) or unaltered in sham operated controls (Group C) in skeletally mature female sheep, aged 2,4 years. A series of intravenous fluorochromes were given to label bone formation and fuchsin-stained microdamage assessed at intervals of up to 24 weeks. Microcracks were present in all groups and were found in the original cortex near the periosteal surface. No microcracks were found in the new, fibrolamellar bone laid down at periosteal or endosteal surfaces. Mean microcrack length (49 µm, SD 10 µm) did not differ between groups or over time. Microcrack numerical and surface densities and resorption cavity density peaked in all groups at 6 weeks, consistent with a regional acceleratory phenomenon (RAP), but the peaks were significantly greater in Group O. The density of refilling or secondary osteons peaked at 10 weeks and the mean time required for the formation of an osteon was 7.51 ± 0.59 weeks. Fatigue-induced microdamage is normally present in bone and is increased due to repetitive loading of the mechanically overloaded radius. The location and timing of microcracks, resorption cavities and secondary osteons are consistent with the activation-resorption-formation remodelling cycle and suggest that microdamage is a stimulus for bone remodelling. [source] Fungal flora associated with Tomicus piniperda L. in an area close to a timber yard in southern PolandJOURNAL OF APPLIED ENTOMOLOGY, Issue 8 2007R. Jankowiak Abstract:, The association between Tomicus piniperda L. (Col., Scolytinae) and fungi was studied in a Pinus sylvestris L. forest in Mielec-Mo,ciska. Fungi were isolated from overwintered adult beetles taken from two stands situated in different distance from timber yard. Two media were used for isolation. The results showed great diversity of fungi associated with T. piniperda: 1895 cultures, representing 64 species, were isolated. Penicillia and Hormonema dematioides were the dominant species, found in 20.2% and 17.8% of all beetles, respectively. A frequently isolated ophiostomatoid fungi was Ophiostoma minus. Qualitative and quantitative differences in the mycobiota composition of this insect between two stands were detected. The highest richness and diversity of fungal species appeared in the samples taken from the location where the trees were heavily damaged by shoot-feeding of T. piniperda. Differences were most clear for the pathogenic O. minus, which was a common fungal associate of the insects in this stand. [source] Did the introduction of maize into Europe provide enemy-free space to Ostrinia nubilalis?JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2010Parasitism differences between two sibling species of the genus Ostrinia Abstract We examined whether maize offers enemy-free space (EFS) to its pest Ostrinia nubilalis, and may thereby have contributed to its divergence from the sibling species, Ostrinia scapulalis, feeding mainly on mugwort, when introduced into Europe five centuries ago. We collected Ostrinia larvae on maize (70 populations, 8425 individuals) and mugwort (10 populations, 1184 individuals) and recorded parasitism using both traditional (counting emerging parasitoids) and molecular methods (detection by specific polymerase chain reaction). The main parasitoid was Macrocentrus cingulum (Braconidae). On mugwort, parasitism was twice that on maize, and parasitoid-related mortality was 8 times higher. This suggests that maize affords substantial EFS to Ostrinia feeding on it. The lower Mortality:Infestation ratio in maize suggests that O. nubilalis' immune response might be stronger than that of O. scapulalis. If so, adapting to maize and diverging from O. scapulalis would decrease the impact of parasitism on O. nubilalis at both ecological and evolutionary levels. [source] A study of dietary advice and care provided to HIV positive patients referred for lipid lowering: as part of a service improvement initiativeJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2008N.A. Billing Background:, Combination antiretroviral therapy (ART) has dramatically reduced mortality in HIV-infected patients. As life expectancy of HIV infected patients has increased, concerns about the long-term effects of treatment grow (Sax, 2006). HIV positive patients have a greater risk of myocardial infarction (MI) and ART has been associated with a 26% increase in the rate of MI per year of exposure (DAD Study Group, 2003). The aim of this study was to evaluate provision of dietetic care to patients referred for lipid lowering advice and identify potential areas for service improvement. Methods:, Departmental activity statistics identified 117 new clients referred for lipid lowering advice in the previous 11 months. The biochemical data and dietetic record cards were screened, of the initial sample 30 were excluded as they did not have follow up biochemistry after their dietetic consultation and a further seven were excluded as they were seen primarily for other conditions. The remaining cards (n = 80) had their dietetic record cards audited to check dietary topics discussed, risk factors identified length before follow up and clinical outcomes. Results:, There were 68 men and 12 women in this sample with a mean age of 46 years and mean body mass index (BMI) of 25.4 kg m,2 (3.7 kg m,2). Of the clients referred, only 48.8% of the sample had high density lipoprotein (HDL): cholesterol ratios taken to calculate cardiovascular risk and most patients were seen an average of 30.7 days (35.3 days) after high was identified. Following their dietetic consultation, 77% of clients had a reduction in their cholesterol levels and 61% had a reduction in triglyceride levels. This sample's average percentage change in cholesterol was ,10% (16%) and triglyceride was ,6% (32%). The most popular dietary advice was reducing saturated fat intake (90%), increasing fibre intake (76%), benefits of plant stanols (40%), importance of regular meals (29%), exercise (26%) and benefits of omega three (11%). Additional risk factors identified 11% of clients seen were smokers, however most records (66%) did not have documentation on whether smoking behaviour was discussed. Only 20% of clients had a follow up appointments and not all were seen within 3 months with average time between follow up being 14.9 weeks (13.2 weeks). Discussion:, Improvement in biochemical results were comparable to a study by Henry et al., (1998) which showed that in HIV infected clients receiving ART, diet modification and increased exercise were successful in reducing cholesterol levels by 11% and triglyceride levels by 21%. The level of smoking was considerably lower than other studies (DAD Study Group, 2003) which reported 56% of HIV positive clients to be smokers. A large number of clients were lost to follow up and were not seen within 3 months. Lazzaretti et al., (2007) showed in a randomized trial that seeing patients at regular 3 month intervals for dietary intervention prevented an increase in lipid blood levels in individuals who start ART. Conclusions:, Not all clients are having their cardiovascular risk calculated before referral for dietary advice. Clients are not being seen at regular intervals by dietitians, some are lost to follow up and smoking status is not regularly documented during dietetic consultation. References, Data Collection on Adverse Events of Anti-HIV Drugs (DAD) Study Group. (2003) Combination antiretroviral therapy and the risk of myocardial infarction. N. Engl. J. Med.349, 1993,2003. Friis-Moller, N., Weber, R., Reiss, P., Thiebaut, R., Kirk, O., d'Arminio, M.A. et al. (2003) Cardiovascular disease risk factors in HIV patients' association with antiretroviral therapy. Results from the DAD study. AIDS17, 1179,1193. Henry, K., Melroe, H., Huebesch, J., Hermundson, J. & Simpson, J. (1998) Atorvastatin and gemfibrozil for protease inhibitor-related lipid abnormalities. Lancet352, 1031,1032. Sax, P.E. (2006)Strategies for management and treatment of dyslipidemia in HIV/AIDS. AIDS Care 18, 149,157. Lazzaretti, R., Pinto-Ribeiro, J., Kummer, R., Polanczyk, C. & Sprinz, E. (2007) Dietary intervention when starting HAART prevents the increase in lipids independently of drug regimen: a randomized trial. Oral abstract session: 4th IAS Conference on HIV Pathogenesis, Treatment and Prevention: Abstract no.WEAB303. [source] The role of gene,environment interaction in the aetiology of human cancer: examples from cancers of the large bowel, lung and breastJOURNAL OF INTERNAL MEDICINE, Issue 6 2001L. A. Mucci Abstract. Mucci LA, Wedren S, Tamimi RM, Trichopoulos D, Adami H.-O. (Harvard School of Public Health, Boston, MA, USA; and Karolinska Institutet, Stockholm, Sweden) The role of gene,environment interaction in the aetiology of human cancer: examples from cancers of the large bowel, lung and breast. J Intern Med 2001; 249: 477,493. It has become increasingly clear that cancer can be considered neither purely genetic nor purely environmental. A relatively new area of cancer research has focused on the interaction between genes and environment in the same causal mechanism. Primary candidates for gene-environment interaction studies have been genes that encode enzymes involved in the metabolism of established cancer risk factors. There are common variant forms of these genes (polymorphisms), which may alter metabolism and increase or decrease exposure to carcinogens, thus impacting the risk of cancer. We present an overview of enzymes involved in carcinogen metabolism, present epidemiological tools to evaluate gene-environment interactions, and provide examples from cancers of the breast, lung and large bowel. [source] Effects of two contrasting agricultural land-use practices on nitrogen leaching in a sandy soil of Middle GermanyJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 3 2009Christian Böhm Abstract The objective of this study is to evaluate different agricultural land-use practices in terms of N leaching and to give recommendations for a sustainable agriculture on sandy soils in Middle Germany. Soil mineral N (Nmin) and leachate N were quantified at a sandy soil in N Saxony during 3 years. Two treatments were applied: intensive (I),using inorganic and organic fertilizer and pesticides, and organic (O),exclusively using organic fertilizer, legume-based crop rotation, and no pesticides. Split application of mineral fertilizers did not result in substantial N losses at treatment I. Legumes induced a considerable increase of soil mineral N and particularly of leachate mineral N (Nmin_perc) at treatment O. High Nmin_perc concentrations (up to 78 mg N L,1) were observed during as well as after the cultivation of legumes. These high Nmin_perc concentrations are the reason why clearly higher Nmin_perc losses were determined at treatment O (62 kg N ha,1 y,1) compared to treatment I (23,kg N ha,1 y,1). At both treatments, the quantity of N losses was strongly affected by the precipitation rates. Concentrations and losses of dissolved organic N (DONperc) were assessed as above average at both treatments. The results suggest that the DONperc concentration is influenced by precipitation, soil coverage, and organic fertilizers. Higher values were determined in the percolation water of treatment O. The average annual DONperc losses amounted to 15,kg N ha,1 at I and to 32 kg N ha,1 at O. The average monthly percentage of DONperc losses on the loss of the dissolved total N of percolation water (DTNperc) ranged between <1% and 55% at O and between 2% and 56% at I. For the whole measuring period of 29 months, the relative amounts of DONperc of DTNperc (21% at O and 25% at I) were more or less the same for both treatments. The results show that DONperc can contribute significantly to the total N loss, confirming the importance to consider this N fraction in N-leaching studies. It was concluded that at sandy sites, a split application of mineral fertilizers, as applied at treatment I, seems to be more expedient for limiting the N leaching losses than legume-based crop rotations. [source] Hydrologic Modeling of an Extreme Flood in the Guadalupe River in Texas,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2010Hatim O. Sharif Sharif, Hatim O., Almoutaz A. Hassan, Sazzad Bin-Shafique, Hongjie Xie, and Jon Zeitler, 2010. Hydrologic Modeling of an Extreme Flood in the Guadalupe River in Texas. Journal of the American Water Resources Association (JAWRA) 1-11. DOI: 10.1111/j.1752-1688.2010.00459.x Abstract:, Many of the storms creating the greatest rainfall depths in Texas, measured over durations ranging from one minute to 48 hours, have occurred in the Texas Hill Country area. The upstream portion of the Guadalupe River Basin, located in the Texas Hill Country, is susceptible to flooding and rapid runoff due to thin soils, exposed bedrock, and sparse vegetation, in addition to the Balcones Escarpment uplift contributing to precipitation enhancement. In November 2004, a moist air mass from the Gulf of Mexico combined with moist air from the Pacific Ocean resulted in the wettest November in Texas since 1895. Although the peak discharges were not the highest on record, the U.S. Geological Survey (USGS) stream gauge on the Guadalupe River at Gonzales, Texas reported a daily mean discharge of 2,304 m3/s on November 23, 2004 (average discharge is 53 m3/s). In this paper, we examine the meteorological conditions that led to this event and apply a two-dimensional, physically based, distributed-parameter hydrologic model to simulate the response of a portion of the basin during this event. The study results clearly demonstrate the ability of physically based, distributed-parameter simulations, driven by operational radar rainfall products, to adequately model the cumulative effect of two rainfall events and route inflows from three upstream watersheds without the need for significant calibration. [source] The disposition of free and niosomally encapsulated Rac-flurbiprofen in dairy bovinesJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2010E. O. CONFALONIERI Confalonieri, E. O., Soraci, A. L., Becaluba, M., Denzoin, L., Rodriguez, E., Riccio, B., Tapia, O. The disposition of free and niosomally encapsulated Rac-flurbiprofen in dairy bovines. J. vet. Pharmacol. Therap. 33, 9,14. Pharmacokinetic parameters were established for flurbiprofen (FBP) after intravenous (i.v.) administration (0.5 mg/kg) of niosomal and nonniosomal formulations in dairy cattle. Niosomes of FBP showed a drug loading of 92.0 ± 0.7% and the intravenous administration of the FBP niosomes to dairy cattle did not produce any immunological reaction associated to niosomal components. Niosomal FBP was slowly eliminated from plasma and mean residual time (MRT) and AUC0,t and t 1/2 values were significantly higher than those for non niosomal FBP formulations. The results presented in this study indicate that the long circulation of FBP niosomes offers a potential application for improving the pharmacokinetic parameters of short half-life drugs for clinical use. Niosomes offer new promising perspectives of drug delivery modules in bovine therapeutics. [source] Origin of water in the terrestrial planetsMETEORITICS & PLANETARY SCIENCE, Issue 4 2005Michael J. DRAKE Late-stage delivery of water from asteroidal and cometary sources appears to be ruled out by isotopic and molecular ratio considerations, unless either comets and asteroids currently sampled spectroscopically and by meteorites are unlike those falling to Earth 4.5 Ga ago, or our measurements are not representative of those bodies. However, the terrestrial planets were bathed in a gas of H, He, and O. The dominant gas phase species were H2, He, H2 O, and CO. Thus, grains in the accretion disk must have been exposed to and adsorbed H2 and water. Here I conduct a preliminary analysis of the efficacy of nebular gas adsorption as a mechanism by which the terrestrial planets accreted "wet." A simple model suggests that grains accreted to Earth could have adsorbed 1-3 Earth oceans of water. The fraction of this water retained during accretion is unknown, but these results suggest that examining the role of adsorption of water vapor onto grains in the accretion disk bears further study. [source] Infection of Arabidopsis thaliana leaves with Albugo candida (white blister rust) causes a reprogramming of host metabolismMOLECULAR PLANT PATHOLOGY, Issue 2 2000Hsueh-Mei Chou Albugo candida (Pers.) (O.) Kunze is a biotrophic pathogen which infects the crucifer Arabidopsis thaliana (L.) Heynh forming discrete areas of infection. Eight days after inoculation of leaves, white blisters became visible on the under surface of the leaf although no symptoms were apparent on the upper surface. By day 14, the region of leaf invaded by fungal mycelium had become chlorotic. Recently it has been hypothesized that an accumulation of soluble carbohydrates, following an increase in invertase activity, may trigger sugar signal transduction pathways leading to the repression of photosynthetic gene expression and to the induction of defence proteins. This hypothesis was investigated by quantifying localized changes in carbohydrate and photosynthetic metabolism and the expression of genes encoding photosynthetic and defence proteins. Quantitative imaging of chlorophyll fluorescence revealed that the rate of photosynthesis declined progressively in the invaded regions of the leaf. However, in uninfected regions of the infected leaf the rate of photosynthesis was similar to that measured in the control leaf until late on during the infection cycle when it declined. Images of nonphotochemical fluorescence quenching (NPQ) suggested that the capacity of the Calvin cycle had been reduced in infected regions and that there was a complex metabolic heterogeneity within the infected leaf. A. candida also caused localized changes in the carbohydrate metabolism of the leaf; soluble carbohydrates accumulated in the infected region whereas the amount of starch declined. The reverse was seen in uninfected regions of the infected leaf; carbohydrates did not accumulate until late on during infection and the amount of starch increased as the infection progressed. There was an increase in the activity of invertases which was confined to regions of the leaf invaded by the fungal mycelium. The increase in apoplastic invertase activity was of host origin, as mRNA levels of the AT,FRUCT1 gene (measured by semiquantitative RT-PCR) increased 40-fold in the infected region. The increase in soluble invertase activity resulted from the appearance of a new isoform in the invaded region of the leaf. Current evidence suggests that this was of fungal origin. Northern blot analysis of cab and rbcS showed that photosynthetic gene expression was repressed in the infected leaf from 6 days after inoculation (DAI) when compared to control leaves. In contrast, there was no detectable induction of defence proteins in the infected leaf. These data are discussed in the context of the sugar-sensing hypothesis presented above. [source] Grass blades as tree rings: environmentally induced changes in the oxygen isotope ratio of cellulose along the length of grass bladesNEW PHYTOLOGIST, Issue 3 2002Brent R. Helliker Summary ,,In this study, we tested the hypothesis that environmentally induced changes in the oxygen isotope ratio of leaf water are recorded in grass blade cellulose during leaf-blade expansion. ,,Grasses were grown hydroponically in chambers that allowed for control of relative humidity while keeping isotopic inputs (namely source water) constant. ,,In experiments where relative humidity was changed from 35% to 93% during grass blade expansion, a 10, shift in cellulose , 18 O was observed along single grass blades of Lolium multiflorum . However, statistically significant changes were not detectable with relative humidity of 93% to 70%. ,,It is shown that grass blades, analogously to tree rings, record environmental change on an interseasonal basis. In light of this, care must be taken to compare leaves of the same developmental stage to avoid confusion of environmental effects with physiological effects in interpretations of leaf organic material , 18 O. The results presented here confirm the ability of the current empirical models to predict the oxygen isotope ratio of cellulose in both grass blades that expanded in constant and variable growth conditions. [source] Co-occurrence of ectoparasites on rodent hosts: null model analyses of data from three continentsOIKOS, Issue 1 2010Boris R. Krasnov We studied patterns of species co-occurrence in communities of ectoparasitic arthropods (ixodid ticks, mesostigmate mites and fleas) harboured by rodent hosts from South Africa (Rhabdomys pumilio), South America (Scapteromys aquaticus and Oxymycterus rufus) and west Siberia (Apodemus agrarius, Microtus gregalis, Microtus oeconomus and Myodes rutilus) using null models. We compared frequencies of co-occurrences of parasite species or higher taxa across host individuals with those expected by chance. When non-randomness of parasite co-occurrences was detected, positive but not negative co-occurrences of parasite species or higher taxa prevailed (except for a single sample of mesostigmate mites from O. rufus). Frequency of detection of non-randomness of parasite co-occurrences differed among parasite taxa, being higher in fleas and lower in mites and ticks. This frequency differed also among host species independent of parasite taxon, being highest in Microtus species and lowest in O. rufus and S. aquaticus. We concluded that the pattern of species co-occurrence in ectoparasite communities on rodent hosts is predominantly positive, depends on life history of parasites and may be affected to a great extent by life history of a host. [source] Compatibility of Automatic Threshold Tracking Pacemakers with Previously Implanted Pacing Leads in ChildrenPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2002OSMAN KUCUKOSMANOGLU KUCUKOSMANOGLU, O., et al.: Compatibility of Automatic Threshold Tracking Pacemakers with Previously Implanted Pacing Leads in Children. The Autocapture function controls and optimizes the amplitude of the pacing pulse and saves energy. The manufacturer recommends using a special low polarization, low threshold bipolar Pacesetter lead for the Autocapture function. The purpose of this study was to evaluate the compatibility of Autocapture with previously implanted pacing leads. The study included 15 patients (mean age 13.6 ± 3.4 years) who needed pulse generator replacement and received the VVIR pacemaker Regency SR+ or the DDDR pacemakers Affinity DR or Integrity DR with the Autocapture function. The new pulse generators connected to previously implanted ventricular leads. At the time of implantation the pacing threshold was 1.0 ± 0.35 V at 0.5 ms, the lead impedance was 580 ± 80 ,, and the spontaneous R wave amplitude was 7.89 ± 4.89 mV. The polarization signal (PS) was 3.8 ± 3.04 mV, and evoked response (ER) was 8.15 ± 4.57 mV at the predischarge testing. Follow-up telemetry was done at months 1, 3, 6, 12, and 18. The follow-up duration was 9.4 ± 5 months (range 1,18 months). If the results of PS and ER measurements were acceptable for Autocapture, it turned on at the 1-month visit. In six (40%) patients the results were found acceptable for Autocapture function. Age, lead impedance, pacing threshold, intrinsic R wave measurement, lead age, fixation mechanism, and ER measurements were not statistically different in Autocapture suitable and not suitable groups. The main reason not to activate Autocapture had been increased PS. Any significant fluctuations were not observed in pacing threshold, lead impedance, ER, and PS during follow-up. In conclusion, previously implanted pacing leads may be compatible with the Autocapture function. [source] When Should Heparin Preferably Be Administered During Radiofrequency Catheter Ablation?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2001OLE-GUNNAR ANFINSEN ANFINSEN, O.-G., et al.: When Should Heparin Preferably be Administered During Radiofrequency Catheter Ablation? RF catheter ablation is complicated by thromboembolism in about 1% of patients. Limited knowledge exists concerning when and how to use anticoagulation or antithrombotic treatment. We studied the activation of coagulation (prothrombin fragment 1 + 2 [PF1 + 2] and D-dimer), platelets (,-thromboglobulin [,-TG]) and fibrinolysis (plasmin-antiplasmin complexes [PAP]) during RF ablation of accessory pathways in 30 patients. They were randomized to receive heparin (100 IU/kg, intravenously) (1) immediately after introduction of the femoral venous sheaths (group I) or (2) after the initial electrophysiological study, prior to the delivery of RF current (groups II and III). Group II additionally received saline irrigation of all femoral sheaths. After the initial bolus, 1,000 IU of heparin was supplied hourly in all groups. Within groups II and III, median plasma values of PF1 + 2 and ,-TG more than tripled (P , 0.007) during the diagnostic study and gradually declined during heparin administration despite RF current delivery. Median D-dimer tripled (P = 0.005) and PAP doubled (NS) before heparin administration; then both remained around the upper reference values. In the early heparin group, however, PF1 + 2, Ddimer, and PAP did not rise at all, and ,-TG showed only a slight increase towards the end of the procedure. The differences between group I versus groups II and III were statistically significant prior to the first RF current delivery (PF1 + 2, D-dimer, and ,-TG) and by the end of the procedure (PF1 + 2, D-dimer, and PAP). In conclusion, "late" heparin administration allows hemostatic activation during the initial catheterization and diagnostic study. By administering intravenous heparin immediately after introduction of the venous sheaths, hemostatic activation is significantly decreased. Saline irrigation of the venous sheaths added nothing to late heparin administration. [source] Differential seedling resistance to the eyespot pathogens, Oculimacula yallundae and Oculimacula acuformis, conferred by Pch2 in wheat and among accessions of Triticum monococcumPLANT PATHOLOGY, Issue 5 2010C. Burt Eyespot is an economically important stem-base disease of wheat caused by two fungal species: Oculimacula yallundae and Oculimacula acuformis. This study investigated the efficacy of two sources of resistance, viz. the genes Pch1, introgressed into hexaploid wheat from Aegilops ventricosa, and Pch2, identified in wheat cv. Cappelle Desprez, against O. yallundae and O. acuformis separately. In a series of seedling bioassays Pch1 was found to be highly effective against both species. Although Pch2 was found to confer resistance against both pathogen species, it was significantly less effective against penetration from O. yallundae than O. acuformis. Furthermore, a quantitative trait locus (QTL) analysis was not able to locate any resistance to O. yallundae on chromosome 7A of Cappelle Desprez. This has important implications for the use of Pch2 in commercial cultivars as it is necessary to have genes that confer resistance to both pathogens for effective eyespot control. In addition, a set of 22 T. monococcum accessions was screened for resistance to both O. yallundae and O. acuformis to identify potentially novel resistances and to assess the accessions for evidence of differential resistance to the eyespot species. Significant differences in resistance to the two pathogens were identified in four of these lines, providing evidence for differential resistance in T. monococcum. This study demonstrates that future screening for novel sources of eyespot resistance should investigate both pathogen species. [source] Effects of growth and virulence of associated blue-stain fungi on host colonization behaviour of the pine shoot beetles Tomicus minor and T. piniperdaPLANT PATHOLOGY, Issue 1 2001H. Solheim The pine shoot beetles Tomicus minor and T. piniperda are common in the Nordic countries. Of these, T. piniperda may attack and kill living but severely stressed trees, whereas T. minor has never been reported to be individually responsible for killing live trees. Both species are associated with blue-stain fungi: T. minor with Ophiostoma canum and T. piniperda with Leptographium wingfieldii and Ophiostoma minus. The growth of these fungi was studied in phloem and sapwood of live Scots pine trees, on malt agar, and on malt agar under oxygen-deficient conditions. Leptographium wingfieldii was more virulent (i.e. caused more extensive host symptoms) grew more quickly on malt agar, and was less affected by oxygen-deficient growth conditions than either O. minus or O. canum. Ophiostoma canum was least virulent. In low-density inoculations it induced lesions similar to those induced by sterile control inoculations; it grew very slowly on malt agar and stopped growing after ,30 mm under oxygen-deficient conditions. Ophiostoma minus was intermediate in all respects. The different virulence of the blue-stain fungi associated with the two pine shoot beetles may explain the lower level of aggressiveness in T. minor. [source] REVIEW ARTICLE: The Unique Properties of Uterine NK CellsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2010Irit Manaster Citation Manaster I, Mandelboim O. The unique properties of uterine NK cells. Am J Reprod Immunol 2009 Abstract Natural killer (NK) cells are lymphocytes of the innate immunity system that are able to kill various hazardous pathogens and tumors. However, it is now widely accepted that NK cells also possess non-destructive functions, as has been demonstrated for uterine NK cells. Here, we review the unique properties of the NK cells in the uterine mucosa, prior to and during pregnancy. We discuss the phenotype and function of mouse and human endometrial and decidual NK cells and suggest that the major function of decidual NK cells is to assist in fetal development. We further discuss the origin of decidual NK cells and suggest several possibilities that might explain their accumulation in the decidua during pregnancy. [source] Growth, salinity tolerance and microsatellite analysis of the F2 reciprocal hybrids of Oreochromis niloticus×Sarotherodon galilaeus at different salinitiesAQUACULTURE RESEARCH, Issue 9 2010Biao Yan Abstract Oreochromisniloticus (O), the sixth generation of Genetic Improvement of Farmed Tilapia, shows rapid growth but poor salt tolerance, while Sarotherodon galilaeus (S) exhibits opposite traits. To combine the traits, F1 progeny was obtained through artificial fertilization. Fertile F1 produced F2 by natural spawning. The mean survival times, the median survival time (ST50) or the survival rate of hybrids was greater than O. niloticus in a gradual or an acute salinity change. Plasma osmolarity, [Na+] and [Cl,] of the hybrids fluctuated in 32 g L,1 water during a 24-h period, but eventually reached levels similar to fish in freshwater. O. niloticus,×S. galilaeus, (OS F2) or S. galilaeus,×O. niloticus, (SO F2) showed the fastest growth at 22.5 g L,1, equal to about 78.2% or 69.7% of O. niloticus at 0 and 3.87 or 3.45 times that of S. galilaeus at their individual optimum growth. Growth in OS F2 was 12% faster than SO F2. Microsatellite analysis showed that F2 had more alleles, a higher polymorphism information content and greater observed and expected heterozygosity than O. or S. Population differentiation was not detected between F1 and F2. All the results indicated that F2 could be exploited for commercial production under saline conditions. [source] Estimating the human impact on populations of the endangered noble crayfish (Astacus astacus L.) in north-western PolandAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2006Holger K. Schulz Abstract 1.The Pomorskie Lakeland close to the town of Miastko shows the highest density of stocks of the noble crayfish Astacus astacus (L.) in the lowlands of north-western Poland. In summer 2002, the present status of this highly threatened species was analysed by means of mark and recapture trapping. 2.Nine lakes with known occurrence of A. astacus were investigated. Each lake was surveyed with regard to the crayfish population density, water quality and potential recent and historical impact of fisheries and recreation. The estimated population density was evaluated statistically with respect to a set of potential environmental variables. 3.The estimated densities of A. astacus populations varied from very abundant (6.6 adult individuals per trap per night) to absent. Two lakes were found to contain the non-indigenous crayfish Orconectes limosus (Raf.). The population density was not correlated with conductivity, pH, transparency, alkalinity, the concentration of ammonium, calcium, chloride, nitrate, nitrite, total nitrogen, total phosphorus, or with the trophic status of the lakes. A. astacus occurred in lakes ranging from mesotrophic to eutrophic. 4.The results suggest that both occurrence and density of A. astacus populations depended on criteria associated with human activities that have altered the aquatic environment. Abundance of A. astacus was negatively correlated with eel (Anguilla anguilla) stocking intensity (r = ,0.88; p < 0.01) and number of yearly net catches (r = ,0.66; p < 0.05) and positively correlated with distance to nearest town (r = 0.72; p < 0.05). 5.It is concluded that the introduction of O. limosus most likely resulted from fishery activities, emphasizing the need for regulations to reduce the negative impact of lake fisheries on native crayfish stocks. Copyright © 2005 John Wiley & Sons, Ltd. [source] Diversity of detoxification pathways of ingested ecdysteroids among phytophagous insectsARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2007Kacem Rharrabe Abstract The metabolic pathways of ingested ecdysteroids have been investigated in three insect species, the aphid Myzus persicae and two Lepidoptera, Plodia interpunctella and Ostrinia nubilalis. M. persicae produces mainly a 22-glucoside conjugate, whereas P. interpunctella eliminates a mixture of 20E and its 3-oxo and 3-epi derivatives, both in free form and as conjugates with various fatty acids. O. nubilalis only produces fatty acyl ester conjugates. These data point out the great diversity of detoxification mechanisms used by phytophagous insects in order to overcome the potential harmful effects of ecdysteroids present in their food. Arch. Insect Biochem. Physiol. 65:65,73, 2007. © 2007 Wiley-Liss, Inc. [source] The impact of anterior cruciate ligament injury on lubricin metabolism and the effect of inhibiting tumor necrosis factor , on chondroprotection in an animal modelARTHRITIS & RHEUMATISM, Issue 10 2009K. A. Elsaid Objective To examine the effects of anterior cruciate ligament transection (ACLT) in a rat model on lubricin metabolism and its relationship to markers of inflammation and cartilage damage, and to determine whether blocking the metabolic effects of tumor necrosis factor , (TNF,) by etanercept increases the chondroprotection provided by lubricin. Methods Unilateral ACLT was performed in Lewis rats. Levels of lubricin, TNF,, interleukin-1, (IL-1,), and sulfated glycosaminoglycans (sGAG) in synovial fluid (SF) lavage specimens and synovial tissue lubricin gene expression were evaluated at 1 week and 4 weeks following ACLT. Histologic evaluation of articular cartilage included staining with lubricin-specific monoclonal antibody 9G3 and Safranin O. The percentage of lubricin staining on the surface of articular cartilage in weight-bearing areas was estimated by digital imaging. Blocking of TNF, was performed using etanercept, which was administered subcutaneously at a dose of 0.5 mg/kg around the ACL-transected joints, using different dosing strategies. The ACL-transected and contralateral joints of these rats were harvested 4 weeks following surgery. Results Four weeks following ACLT, SF lubricin concentrations and the percentage of cartilage surface lubricin staining were significantly lower in the injured joints compared with the contralateral joints. A significant decrease in synovial tissue lubricin gene expression was associated with elevated TNF, and IL-1, concentrations in SF lavage samples. With all of the etanercept treatment strategies, blocking of TNF, significantly increased the amount of lubricin bound to cartilage, coupled with a significant decrease in sGAG release. However, changes in the concentrations of lubricin in SF were variable. Conclusion Blocking TNF, resulted in a chondroprotective effect, exemplified by increased lubricin deposition on articular cartilage and a decrease in sGAG release from articular cartilage in an animal model of posttraumatic arthritis. [source] Cover Picture: BioEssays 1/2009BIOESSAYS, Issue 1 2009Article first published online: 22 JAN 200 Cover Photograph: A photograph of Oscarella lobularis in a typical biocoenosis. This common and easily accessible sponge is characterized by relatively simple histology and cell composition, absence of skeleton, and strongly pronounced epithelial structure. On pages tkk-tkk, Ereskovsky et al, detail the specific features that make O. lobularis a promising homoscleromorph sponge model for evolutionary and developmental researchers. [source] The Homoscleromorph sponge Oscarellalobularis, a promising sponge model in evolutionary and developmental biologyBIOESSAYS, Issue 1 2009Model sponge Oscarella lobularis Abstract Sponges branch basally in the metazoan phylogenetic tree and are believed to be composed of four distinct lineages with still uncertain relationships. Indeed, some molecular studies propose that Homoscleromorpha may be a fourth Sponge lineage, distinct from Demospongiae in which they were traditionally classified. They harbour many features that distinguish them from other sponges and are more evocative of those of the eumetazoans. They are notably the only sponges to possess a basement membrane with collagen IV and specialized cell-junctions, thus possessing true epithelia. Among Homoscleromorphs, we have chosen Oscarella lobularis as a model species. This common and easily accessible sponge is characterized by relatively simple histology and cell composition, absence of skeleton, and strongly pronounced epithelial structure. In this review, we explore the specific features that make O. lobularis a promising homoscleromorph sponge model for evolutionary and developmental researches. [source] Solved Problem in Geostatistics by LEUANGTHONG, O., KHAN, K. D., and DEUTSCH, C. V.BIOMETRICS, Issue 3 2009Ole F. Christensen No abstract is available for this article. [source] | ||||||||||||||||||||||||||||||||||