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1.
Carex sect. Spirostachyae comprises 25 species displaying the centre of diversity in Eurasia, while sect. Elatae comprises 22 species displaying the centre of diversity in tropical African mountainous regions. Phylogenetic analysis of the 136 ITS and 108 5′trnK intron sequences of 23 species of sect. Spirostachyae and 20 species of sect. Elatae revealed that neither section is monophyletic. With the exclusion of C. montis-eeka (sect. Spirostachyae) and C. insularis, C. iynx and C. longibrachiata (sect. Elatae), the sects. Spirostachyae and Elatae constitute a monophyletic group of 38 species, 22 of which were previously included in sect. Spirostachyae and 16 of which were in sect. Elatae (considering C. thomasii as C. mannii ssp. thomasii). Two main groups with different edaphic preferences were identified in the core Spirostachyae, in congruence with some morphological features. One group comprises primarily acidophilus species including 11 species of sect. Spirostachyae and 16 species of sect. Elatae. The other group includes 11 basophilic species of sect. Spirostachyae. Incongruence between nuclear and plastid genomes was detected, suggesting hybridization or lineage sorting processes in the evolution of the core Spirostachyae.  相似文献   
2.
Municipal sewage, urban runoff and accidental oil spills are common sources of pollutants in urban mangrove forests and may have drastic effects on the microbial communities inhabiting the sediment. However, studies on microbial communities in the sediment of urban mangroves are largely lacking. In this study, we explored the diversity of bacterial communities in the sediment of three urban mangroves located in Guanabara Bay (Rio de Janeiro, Brazil). Analysis of sediment samples by means of denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene fragments suggested that the overall bacterial diversity was not significantly affected by the different levels of hydrocarbon pollution at each sampling site. However, DGGE and sequence analyses provided evidences that each mangrove sediment displayed a specific structure bacterial community. Although primer sets for Pseudomonas, alphaproteobacterial and actinobacterial groups also amplified ribotypes belonging to taxa not intended to be enriched, sequence analyses of dominant DGGE bands revealed ribotypes related to Alteromonadales, Burkholderiales, Pseudomonadales, Rhodobacterales and Rhodocyclales. Members of these groups were often shown to be involved in aerobic or anaerobic degradation of hydrocarbon pollutants. Many of these sequences were only detected in the sampling sites with high levels of anthropogenic inputs of hydrocarbons. Many dominant DGGE ribotypes showed low levels of sequence identity to known sequences, indicating a large untapped bacterial diversity in mangrove ecosystems.  相似文献   
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Changes in holocentric chromosome number due to fission and fusion have direct and immediate effects on genome structure and recombination rates. These, in turn, may influence ecology and evolutionary trajectories profoundly. Sedges of the genus Carex (Cyperaceae) comprise ca. 2000 species with holocentric chromosomes. The genus exhibits a phenomenal range in the chromosome number (2n = 10 − 132) with almost not polyploidy. In this study, we integrated the most comprehensive cytogenetic and phylogenetic data for sedges with associated climatic and morphological data to investigate the hypothesis that high recombination rates are selected when evolutionary innovation is required, using chromosome number evolution as a proxy for recombination rate. We evaluated Ornstein–Uhlenbeck models to infer shifts in chromosome number equilibrium and selective regime. We also tested the relationship between chromosome number and diversification rates. Our analyses demonstrate significant correlations between morphology and climatic niche and chromosome number in Carex. Nevertheless, the amount of chromosomal variation that we are able to explain is very small. We recognized a large number of shifts in mean chromosome number, but a significantly lower number in climatic niche and morphology. We also detected a peak in diversification rates near intermediate recombination rates. In combination, these analyses point toward the importance of chromosome evolution to the evolutionary history of Carex. Our work suggests that the effect of chromosome evolution on recombination rates, not just on reproductive isolation, may be central to the evolutionary history of sedges.  相似文献   
5.
In this paper, aspects of the reproductive biology of Lutjanus peru that can be used for the fishery management are described. Samples were taken monthly in 1993 and 1994, from commercial catches in the southern coast of Guerrero, Mexico. A global sex ratio of 1:1.37 (M:F) was found, but the sex ratio was highly variable each month. The condition factor, gonadosomatic, hepatosomatic and stomach fullness indexes were analyzed. None of the morphophysiological indexes showed any clear tendency. From 377 gonads, both male and female, five developmental stages were characterized for each sex. L. peru shows asynchronous gonad development and multiple spawning. Two spawning period were observed in 1993 (March, and August-September) and three in 1994 (April-May, July-August, and November), with a maximum in August of both years. Length at first maturity for the females of L. peru was estimated at 295 mm fork length.  相似文献   
6.
Polycyclic aromatic hydrocarbon (PAH) pollutants originating from oil spills and wood and fuel combustion are pollutants which are among the major threats to mangrove ecosystems. In this study, the composition and relative abundance in the sediment bacterial communities of naphthalene dioxygenase (ndo) genes which are important for bacterial adaptation to environmental PAH contamination were investigated. Three urban mangrove sites which had characteristic compositions and levels of PAH compounds in the sediments were selected. The diversity and relative abundance of ndo genes in total community DNA were assessed by a newly developed ndo denaturing gradient gel electrophoresis (DGGE) approach and by PCR amplification with primers targeting ndo genes with subsequent Southern blot hybridization analyses. Bacterial populations inhabiting sediments of urban mangroves under the impact of different sources of PAH contamination harbor distinct ndo genotypes. Sequencing of cloned ndo amplicons comigrating with dominant DGGE bands revealed new ndo genotypes. PCR-Southern blot analysis and ndo DGGE showed that the frequently studied nah and phn genotypes were not detected as dominant ndo types in the mangrove sediments. However, ndo genotypes related to nagAc-like genes were detected, but only in oil-contaminated mangrove sediments. The long-term impact of PAH contamination, together with the specific environmental conditions at each site, may have affected the abundance and diversity of ndo genes in sediments of urban mangroves.  相似文献   
7.
The development of small molecule inhibitors of growth factor receptors, and the discovery of somatic mutations of the tyrosine kinase domain, have resulted in new paradigms for cancer therapy. Digital microscopy is an important tool for surgical pathologists. The achievements in the digital pathology field have modified the workflow of pathomorphology labs, enhanced the pathologist's role in diagnostics, and increased their contribution to personalized targeted medicine. Digital image analysis is now available in a variety of platforms to improve quantification performance of diagnostic pathology. We here describe the state of digital microscopy as it applies to the field of quantitative immunohistochemistry of biomarkers related to the clinical personalized targeted therapy of breast cancer, non-small lung cancer and colorectal cancer: HER-2, EGFR, KRAS and BRAF genes. The information is derived from the experience of the authors and a review of the literature.  相似文献   
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? Changes in chromosome number as a result of fission and fusion in holocentrics have direct and immediate effects on the recombination rate. We investigate the support for the classic hypothesis that environmental stability selects for increased recombination rates. ? We employed a phylogenetic and cytogenetic data set from one of the most diverse angiosperm genera in the world, which has the largest nonpolyploid chromosome radiation (Carex, Cyperaceae; 2n = 12-124; 2100 spp.). We evaluated alternative Ornstein-Uhlenbeck models of chromosome number adaptation to the environment in an information-theoretic framework. ? We found moderate support for a positive influence of lateral inflorescence unit size on chromosome number, which may be selected in a stable environment in which resources for reproductive investment are larger. We found weak support for a positive influence on chromosome number of water-saturated soils and among-month temperature constancy, which would be expected to be negatively select for pioneering species. Chromosome number showed a strong phylogenetic signal. ? We argue that our finding of small but significant effects of life history and ecology is compatible with our original hypothesis regarding selection of optima in recombination rates: low recombination rate is optimal when inmediate fitness is required. By contrast, high recombination rate is optimal when stable environments allow for evolutionary innovation.  相似文献   
10.
BACKGROUND: EURO-TELEPATH is a European COST Action IC0604. It started in 2007 and will end in November 2011. Its main objectives are evaluating and validating the common technological framework and communication standards required to access, transmit, and manage digital medical records by pathologists and other medical specialties in a networked environment. BUSINESS MODELLING: Working Group 1, "Business Modelling in Pathology," has designed main pathology processes - Frozen Study, Formalin Fixed Specimen Study, Telepathology, Cytology, and Autopsy - using Business Process Modelling Notation (BPMN). INFORMATICS STANDARDS IN PATHOLOGY: Working Group 2 has been dedicated to promoting the application of informatics standards in pathology, collaborating with Integrating Healthcare Enterprise (IHE), Digital Imaging and Communications in Medicine (DICOM), Health Level Seven (HL7), and other standardization bodies. CONCLUSIONS: Health terminology standardization research has become a topic of great interest. Future research work should focus on standardizing automatic image analysis and tissue microarrays imaging.  相似文献   
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