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Selected AbstractsDoes the diapause experience of bumblebee queens Bombus terrestris affect colony characteristics?ECOLOGICAL ENTOMOLOGY, Issue 1 2000M. Beekman Summary 1. Bumblebee colonies show much variation in the number of workers, drones, and queens produced. Because this variation prevails even when colonies are kept under identical conditions, it does not seem to be caused by extrinsic factors but rather by differences between founding queens. 2. The most likely factor that could cause differences between queens is diapause. Although colonies are raised under standardised conditions, the queens often experience diapause of different length. If there are costs associated with diapause that influence post-diapause reproduction, the diapause history of the queens could affect colony characteristics. 3. Here, several colony characteristics are compared: number of first and second brood workers; total number of workers, drones, and queens; energy spent on sexuals; sex ratio; rate of worker production; time to emergence of first reproductive; and colony lifetime. Colonies were used where the queens experienced a diapause treatment of 0 (nondiapause queens), 2, and 4 months. 4. Although no proof was found for the existence of costs associated with diapause, the colony characteristics of nondiapause queens were significantly different from those of diapause queens. Colonies of nondiapause queens produced the lowest number of workers but the highest number of young queens. 5. It is argued that these nondiapause colonies are more time-constrained than diapause colonies because nondiapause colonies produce two generations within the same season and should therefore be more efficient in producing sexual offspring. 6. Moreover, nondiapause colonies should rear a more female-biased sex ratio because they can be certain of the presence of males produced by other (diapause) colonies. [source] Gradients of coastal fish farm effluents and their effect on coral reef microbesENVIRONMENTAL MICROBIOLOGY, Issue 9 2008Melissa Garren Summary Coastal milkfish (Chanos chanos) farming may be a source of organic matter enrichment for coral reefs in Bolinao, Republic of the Philippines. Interactions among microbial communities associated with the water column, corals and milkfish feces can provide insight into the ecosystem's response to enrichment. Samples were collected at sites along a transect that extended from suspended milkfish pens into the coral reef. Water was characterized by steep gradients in the concentrations of dissolved organic carbon (70,160 ,M), total dissolved nitrogen (7,40 ,M), chlorophyll a (0.25,10 ,g l,1), particulate matter (106,832 ,g l,1), bacteria (5 × 105,1 × 106 cells ml,1) and viruses (1,7 × 107 ml,1) that correlated with distance from the fish cages. Particle-attached bacteria, which were observed by scanning laser confocal microscopy, increased across the gradient from < 0.1% to 5.6% of total bacteria at the fish pens. Analyses of 16S rRNA genes by denaturing gradient gel electrophoresis and environmental clone libraries revealed distinct microbial communities for each sample type. Coral libraries had the greatest number of phyla represented (range: 6,8) while fish feces contained the lowest number (3). Coral libraries also had the greatest number of ,novel' sequences (defined as < 93% similar to any sequence in the NCBI nt database; 29% compared with 3% and 5% in the feces and seawater libraries respectively). Despite the differences in microbial community composition, some 16S rRNA sequences co-occurred across sample types including Acinetobacter sp. and Ralstonia sp. Such patterns raise the question of whether bacteria might be transported from the fish pens to corals or if microenvironments at the fish pens and on the corals select for the same phylotypes. Understanding the underlying mechanisms of effluent,coral interactions will help predict the ability of coral reef ecosystems to resist and rebound from organic matter enrichment. [source] Identification of a novel single nucleotide polymorphism in the first tandem repeat sequence of the thymidylate synthase 2R alleleINTERNATIONAL JOURNAL OF CANCER, Issue 9 2007Lisa F. Lincz Abstract Thymidylate synthase (TS) activity is an important determinant of response to chemotherapy with fluoropyrimidine prodrugs and its expression is largely determined by the number of functional upstream stimulatory factor (USF) E-box consensus elements present in the 5,regulatory region of the TYMS gene. Two known polymorphisms in this area, a variable number of tandem repeat (VNTR) consisting of 2 or 3 repeats (2R/3R) of a 28-bp sequence and a further G > C single nucleotide substitution within the second repeat of the 3R, result in genotypes with between 2 and 4 functional repeats in most humans. Here, we identify a further G > C SNP in the first repeat of the TYMS 2R allele, which effectively abolishes the only functional USF protein binding site in this promoter. The frequency of the new allele was found to be 4.2% (95% CI = 1.4,9.6%), accounting for 8.8% (95% CI = 2.9,19.3%) of all 2R alleles in our patient cohort. Thus, we observed that the lowest number of inherited functional binding sites is 1 instead of 2 as previously thought, and could potentially be 0 in a homozygous individual. This would severely decrease TS expression and may have implications for predicting efficacy and toxicity of therapy with commonly used fluorouracil-based therapy regimes. © 2007 Wiley-Liss, Inc. [source] The function of mate choice in sticklebacks: optimizing Mhc genetics,JOURNAL OF FISH BIOLOGY, Issue 2003M. Milinski Sexual reproduction is an evolutionary ,puzzle'. A sexual female ,throws away' half of her genes (during meiosis), and ,fills up' what she lost with genes from a male. Thus, sexual reproduction can only be successful if the offspring with the new mixture of genes should be more than twice as fit as if she had just made a copy of herself. A challenging hypothesis assumes that infectious diseases select for females that reshuffle the immune genes for their offspring in each generation. The required increase in quality could be achieved by females selectively ,smelling out' suitable immune-genes (i.e. Mhc alleles) in potential partners, which, in combination with the female's genes, offer optimal resistance against quickly changing infectious diseases. It was found that most three spined sticklebacks Gasterosteus aculeatus in natural populations around Plön, Germany, had intermediate instead of maximal numbers of different Mhc class IIB alleles. Furthermore, fish with an intermediate number of different Mhc alleles were infected with the lowest number of both parasite species and parasites per species. This suggests that Mhc heterozygosity was optimized instead of maximized. Can this immunogenetic optimum be achieved through female choice? In a flow channel design that allowed the detection of olfactory signals only, it was found that female three-spined sticklebacks that were ready to spawn preferred males as mates that in combination with their Mhc alleles would allow the production of offspring with the optimal number of Mhc alleles. Thus, mate choice in three-spined sticklebacks could have the two-fold advantage over asexual reproduction that is required to maintain sexual reproduction. The interaction of olfactory with visual signals in three-spined stickleback mate choice is discussed. The three-spined stickleback is a suitable model organism for studying the evolution of sexual reproduction in relation to optimizing offspring immune genetics although other fishes may be as suitable. [source] Genetic characteristics of hepatitis B virus genotypes as a factor for interferon-induced HBeAg clearanceJOURNAL OF MEDICAL VIROLOGY, Issue 8 2007Jinlin Hou Abstract The factors determining the responsiveness of different hepatitis B virus (HBV) genotypes to interferon treatment are not fully understood. We investigated the relationship between HBV genetic characteristics and the outcome of short (16 weeks) or prolonged (32 weeks) treatment with standard interferon-alpha in a prospectively followed cohort of 103 patients across Europe with HBeAg positive chronic hepatitis B. INNO-LiPA assays and HBV DNA sequencing were used to determine HBV genotypes, mutations in the core promoter and precore/core regions. After 16-weeks interferon-alpha treatment, the rate of HBeAg clearance was higher in genotype A versus all other genotypes (P,=,0.014), or genotype D alone (P,=,0.05). The HBV genome analysis revealed that: (i) after 16-weeks treatment, an HBV subpopulation with core promoter mutations emerged or increased (P,<,0.001) only in genotype A; (ii) the core gene of genotype A has the lowest number of amino acid variations in comparison with genotypes B, C, or D. Logistic regression analysis identified genotype A as a positive predictor of short (16 weeks) treatment response (P,=,0.001; odds ratio 6.19, 95 confidence interval 1.94,19.8), having a greater impact than baseline HBV DNA or alanine aminotransferase (ALT) levels. In contrast, the response to prolonged interferon-alpha treatment was not different between HBV genotypes. These results suggest that HBV genotype A responds earlier to interferon treatment than other genotypes, which is associated with its molecular characteristics. The optimal duration of interferon-based therapies in chronic hepatitis B may vary between different HBV genotypes. J. Med. Virol. 79: 1055,1063, 2007. © 2007 Wiley-Liss, Inc. [source] Comparative evaluation of four decontamination protocols for the isolation of Mycobacterium avium subsp. paratuberculosis from milkLETTERS IN APPLIED MICROBIOLOGY, Issue 3 2001L. Dundee Aims:,Four chemical decontamination protocols for milk were compared with respect to mean percentage recovery of spiked Mycobacterium avium subsp. paratuberculosis, minimum detection limit and ease of application. Methods and Results:,Raw milk spiked with 106 cfu M.a. paratuberculosis was decontaminated prior to culture by: (1) treatment with 0·75% (w/v) hexadecylpyridinium chloride (HPC) for 5 h; (2) and (3) Cornell methods employing brain heart infusion broth containing 0·75% (w/v) and 0·9% (w/v) HPC, respectively; and (4) a C18 -carboxypropylbetaine (CB-18Ô) method. The 0·75% HPC method yielded the highest mean percentage recovery of M.a. paratuberculosis (28·7%) and was capable of detecting the lowest number of cells (30 cfu/40 ml). Conclusions:,Treatment of milk with 0·75% HPC for 5 h was shown to be superior to the other methods for decontaminating milk prior to culture for M.a. paratuberculosis. Significance and Impact of Study:,Certain chemical decontamination protocols are too harsh for application to milk. The ,best' decontamination protocol only recovered a fraction of the M.a. paratuberculosis cells present in a milk sample. [source] Determinants of the optimal first-line therapy for follicular lymphoma: A decision analysis,AMERICAN JOURNAL OF HEMATOLOGY, Issue 4 2010Rebecca L. Olin Combination immunochemotherapy is the most common approach for initial therapy of patients with advanced-stage follicular lymphoma, but no consensus exists as to the optimal selection or sequence of available regimens. We undertook this decision analysis to systematically evaluate the parameters affecting the choice of early therapy in patients with this disease. We designed a Markov model incorporating the three most commonly utilized regimens (RCVP, RCHOP, and RFlu) in combinations of first- and second-line therapies, with the endpoint of number of quality-adjusted life years (QALYs) until disease progression. Data sources included Phase II and Phase III trials and literature estimates of long-term toxicities and health state utilities. Meta-analytic methods were used to derive the values and ranges of regimen-related parameters. Based on our model, the strategy associated with the greatest number of expected quality-adjusted life years was treatment with RCHOP in first-line therapy followed by treatment with RFlu in second-line therapy (9.00 QALYs). Strategies containing RCVP either in first- or second-line therapy resulted in the lowest number of QALYs (range 6.24,7.71). Sensitivity analysis used to determine the relative contribution of each model parameter identified PFS after first-line therapy and not short-term QOL as the most important factor in prolonging overall quality-adjusted life years. Our results suggest that regimens associated with a longer PFS provide a greater number of total QALYs, despite their short-term toxicities. For patients without contraindications to any of these regimens, use of a more active regimen may maximize overall quality of life. Am. J. Hematol. 2010. © 2010 Wiley-Liss, Inc. [source] Estimating Genetic Diversity in Durum and Bread Wheat Cultivars from Turkey using AFLP and SAMPL MarkersPLANT BREEDING, Issue 1 2008S. Alt Abstract Since 1925, more than 100 wheat varieties were developed and released in Turkey, and many more were introduced from abroad, but no systematic analysis of their genetic diversity has been performed yet. In this research, a total of 34 domestic and foreign cultivars (12 durum and 22 bread wheats), released in Turkey between 1936 and 2000, were fingerprinted by means of five amplified fragment length polymorphism and three selective amplification of microsatellite polymorphic loci (SAMPL) primer combinations, to evaluate their genetic variation and to determine the existence of cultivar-specific bands. Among the 344 amplicons scored, 214 were polymorphic. The primer combination EACG/MAGG yielded the highest number and the primer combination SAMPL,6/M AGA produced the lowest number of polymorphic bands. Most cultivars were molecularly very similar, although a few distinct ones (the durum wheat ,Kunduru,1149' and the bread wheat ,,kizce,96') were also identified. Seven cultivar-specific markers for different bread wheat cultivars (,Golia', ,Seri,82', ,Adana,99', ,Pandas' and ,Sertak,52') and six cultivar-specific markers for durum wheat cv ,Kunduru' were observed. Our results show that genetic diversity among old and present,day wheat cultivar commonly grown in Turkey is limited. [source] The effect of grade of anaesthetist on outcome after day surgery,ANAESTHESIA, Issue 2 2009J. Hanousek Summary We conducted a retrospective survey to investigate if the grade of anaesthetist was a significant factor in determining outcome after day surgery in a district general hospital. All day surgery procedures performed between 1996 and 2006 were included except those under surgically administered local anaesthetic. The outcome measures assessed were unplanned admissions and symptoms reported after discharge. The overall admission rate was 2.6%, the admission rate for anaesthetic-related reasons was 1.5%, and 49% of patients reported some symptoms after discharge. Over the period studied the admission rate fell from 4.2% to 2.0%, admissions for anaesthetic-related reasons fell from 3.0% to 0.7% and reported symptoms fell from 67% to 37%. Consultants anaesthetists were associated with the lowest unplanned admission rate (consultants 2.3%, staff grade and associate specialists 3.1%, and trainees 3.3%), the lowest admission rate for anaesthetic reasons (consultants 1.2%, staff and associate specialists 2.0%, and trainees 1.8%), lower than expected specialty-weighted admissions and the lowest number of reported symptoms (consultants 47.3%, staff grade and associate specialists 52.6%, trainees 49.0%) (p < 0.001). We conclude that there was an improvement in outcome over the period of study and that the grade of anaesthetist is associated with outcome after day surgery. [source] The Hindlimb Muscles of Rhea americana (Aves, Palaeognathae, Rheidae)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2010M. B. J. Picasso With 13 figures Summary The Greater Rhea is the largest cursorial Ratitae bird native to South America. Due to its increasing importance in farming and therefore in the sustainable use of this species, a comprehensive knowledge of their anatomy is essential. The goal of this study was to provide an anatomical description of the hindlimb muscles of Rhea americana. Six adult birds of both sexes were macroscopically studied analysing the origin and insertion of thigh and shank muscles. The thigh showed the highest number of muscles, whereas the shank showed the lowest number; this feature minimizes inertia and allows achieving high stride frequencies. The muscles of the shank showed long tendons of insertion that reduce the energetic cost during running. The major muscles responsible for extension of the hip and the ankle joints were massive and robust indicating their importance for cursorial locomotion. The pelvic limb muscles of Rhea americana resemble those of other cursorial Ratitae and their features are consistent with specialization for high-speed locomotion. [source] Macrofauna Communities in the Eastern Mediterranean Deep SeaMARINE ECOLOGY, Issue 3 2003Ingrid Kröncke Abstract., During two expeditions with RV ,Meteor' in summer 1993 and winter 1997/98 the structural and functional diversity of the benthic system of the highly oligotrophic eastern Mediterranean deep sea was investigated. The macrofauna communities were dominated by polychaetes even at the deepest stations. The fauna at shallow stations was dominated by surface deposit feeders, whereas subsurface deposit feeders and predators generally increased with depth. A high percentage of suspension-feeding Porifera was found in the Levantine Basin. Mean abundance and number of taxa of both expeditions were significantly correlated to depth and distance to the nearest coast as well as to the total organic carbon (TOC) content in sediments. Numbers of taxa and abundance decreased generally with depth, although lowest numbers were not found at the deepest stations but in the extremely oligotrophic Levantine and Ierapetra Basin. Biomass measured during the second cruise was extremely low in the Ierapetra Basin and comparable to other extreme oligotrophic seas. The significant correlations found for TOC contents and macrofauna with distance to coast during both expeditions apparently reflect the role of hydrographically governed transport of organic matter produced in coastal regions into greater and extreme depths of the Mediterranean Sea. Seasonal differences in macrofauna communities due to seasonal differences in food supply were not found. However, recent large-scale hydrographic changes (Eastern Mediterranean Transient, EMT) might change the oligotrophy and, thus, the structure of the benthic communities in the Eastern Mediterranean deep sea. [source] Concurrent Management of an Exotic Species and Initial Restoration Efforts in ForestsRESTORATION ECOLOGY, Issue 4 2005Stephen D. Murphy Abstract One of the proximate results of forest fragmentation, and a cause of continued microenvironmental change and exacerbation of ecological problems, is increased invasions by weedy plant species. One such example is Alliaria petiolata (Brassicaceae), a serious pest threatening much of eastern North America. Alliaria petiolata impedes mitigation of fragmentation and restoration efforts because it tends to outcompete and possibly extirpate much of the native understory species on localized scales. As part of a strategy to address the problems of fragmented habitats, an experiment was conducted to determine whether Sanguinaria canadensis (Papaveraceae) could outcompete A. petiolata. Using an additive design, I transplanted S. canadensis at densities of 0, 1, 2, 3, 5, 7, 9, 11, 15, and 20 ramets/m2 in 1997 and allowed them to interact with initial A. petiolata densities of 128 seedlings and 31 rosettes/m2. As of 2000, multivariate analyses of variance with repeated measures and simple analyses of variance indicated that initial S. canadensis densities of as little as 5 ramets/m2 suppressed A. petiolata. Initial S. canadensis densities of 9 and 11 ramets/m2 resulted in the lowest numbers of late-spring seedlings, numbers and sizes of year 1 and 2 rosettes, numbers and gross areas of stem leaves, numbers of flowering individuals, number of flowers, number of fruits (siliques), and height at flowering. While it remains to be tested whether this will continue and if the reestablishment of S. canadensis will help reassemble forest ecosystems, the experiments indicated that transplanting S. canadensis was effective at mitigating the spread of A. petiolata. 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