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111.
Tasneem?F.?KhaleelEmail author Rhonda?Dillman Daniel?Gretch 《Sexual plant reproduction》2003,16(1):35-42
Estradiol (E2) was measured in spring and winter tissues in several populations of dioecious Populus tremuloides Michx. and in four trees with perfect flowers. A correlation between the concentration of E2 and sex expression was observed. In catkins, E2 concentrations increased before anthesis, peaked during flowering, and decreased as flowers matured. The increases were concurrent with sporogenesis and development of gametophytes. Statistically significant seasonal variation in E2 concentration was also evident. Dormant winter tissues showed significantly lower E2 concentrations than spring tissues. Branches exposed to relatively more light had significantly higher E2 content in both spring and winter. Seasonal variation in E2 content was also observed in trees of the same sex, among branches of the same tree, and among different organs. 相似文献
112.
Speciation in North American black basses,Micropterus (Actinopterygii: Centrarchidae) 总被引:1,自引:0,他引:1
Near TJ Kassler TW Koppelman JB Dillman CB Philipp DP 《Evolution; international journal of organic evolution》2003,57(7):1610-1621
Abstract.— The Pleistocene Epoch has been frequently cited as a period of intense speciation for a significant portion of temperate continental biotas. To critically assess the role of Pleistocene glaciations on the evolution of the freshwater fish clade Micropterus , we use a phylogenetic analysis of complete gene sequences from two mitochondrial genes (cytochrome b and ND2), and a fossil calibration of the molecular clock to estimate ages of speciation events and rates of diversification. The absence of substantial morphological and ecological divergence together with endemism of five of the eight species in North American tributaries of the Gulf of Mexico may be interpreted as the result of a recent Pleistocene origin for these species. Speciation dates in Micropterus range from 1.01 ± 0.32 to 11.17 ± 1.02 million years ago. Only one speciation event is dated to the Pleistocene, and rates of diversification are not significantly variable in Micropterus. The premise that the Pleistocene was an exceptional period of speciation in Micropterus is not supported. Instead, a Gulf Coast allopatric speciation model is proposed, and predicts periods of dynamic speciation driven by sea level fluctuations in the Late Miocene and Pliocene. The Pleistocene, however, was a period of significant intraspecific mitochondrial lineage diversification. The application of the Gulf Coast allopatric speciation model to the remaining aquatic fauna of the Gulf of Mexico coast in North America will rely on robust phylogenetic hypotheses and accurate age estimations of speciation events. 相似文献
113.
Publication of the complete diploid genome sequence of the yeast Candida albicans will accelerate research into the pathogenesis of Candida infections. Comparative genomic analysis highlights genes that may contribute to C. albicans survival and its fitness as a human commensal and pathogen. 相似文献
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Jan S. Suchodolski Melissa E. Markel Jose F. Garcia-Mazcorro Stefan Unterer Romy M. Heilmann Scot E. Dowd Priyanka Kachroo Ivan Ivanov Yasushi Minamoto Enricka M. Dillman J?rg M. Steiner Audrey K. Cook Linda Toresson 《PloS one》2012,7(12)
Background
Recent molecular studies have revealed a highly complex bacterial assembly in the canine intestinal tract. There is mounting evidence that microbes play an important role in the pathogenesis of acute and chronic enteropathies of dogs, including idiopathic inflammatory bowel disease (IBD). The aim of this study was to characterize the bacterial microbiota in dogs with various gastrointestinal disorders.Methodology/Principal Findings
Fecal samples from healthy dogs (n = 32), dogs with acute non-hemorrhagic diarrhea (NHD; n = 12), dogs with acute hemorrhagic diarrhea (AHD; n = 13), and dogs with active (n = 9) and therapeutically controlled idiopathic IBD (n = 10) were analyzed by 454-pyrosequencing of the 16S rRNA gene and qPCR assays. Dogs with acute diarrhea, especially those with AHD, had the most profound alterations in their microbiome, as significant separations were observed on PCoA plots of unweighted Unifrac distances. Dogs with AHD had significant decreases in Blautia, Ruminococcaceae including Faecalibacterium, and Turicibacter spp., and significant increases in genus Sutterella and Clostridium perfringens when compared to healthy dogs. No significant separation on PCoA plots was observed for the dogs with IBD. Faecalibacterium spp. and Fusobacteria were, however, decreased in the dogs with clinically active IBD, but increased during time periods of clinically insignificant IBD, as defined by a clinical IBD activity index (CIBDAI).Conclusions
Results of this study revealed a bacterial dysbiosis in fecal samples of dogs with various GI disorders. The observed changes in the microbiome differed between acute and chronic disease states. The bacterial groups that were commonly decreased during diarrhea are considered to be important short-chain fatty acid producers and may be important for canine intestinal health. Future studies should correlate these observed phylogenetic differences with functional changes in the intestinal microbiome of dogs with defined disease phenotypes. 相似文献116.
CA Campbell AR Horvath 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2012,33(4):149-160
Timely release and communication of critical test results may have significant impact on medical decisions and subsequent patient outcomes. Laboratories therefore have an important responsibility and contribution to patient safety. Certification, accreditation and regulatory bodies also require that laboratories follow procedures to ensure patient safety, but there is limited guidance on best practices. In Australasia, no specific requirements exist in this area and critical result reporting practices have been demonstrated to be heterogeneous worldwide.Recognising the need for agreed standards and critical limits, the AACB started a quality initiative to harmonise critical result management throughout Australasia. The first step toward harmonisation is to understand current laboratory practices. Fifty eight Australasian laboratories responded to a survey and 36 laboratories shared their critical limits. Findings from this survey are compared to international practices reviewed in various surveys conducted elsewhere. For the successful operation of a critical result management system, critical tests and critical limits must be defined in collaboration with clinicians. Reporting procedures must include how critical results are identified; who can report and who can receive critical results; what is an acceptable timeframe within which results must be delivered or, if reporting fails, what escalation procedures should follow; what communication channels or systems should be used; what should be recorded and how; and how critical result procedures should be maintained and evaluated to assess impact on outcomes.In this paper we review the literature of current standards and recommendations for critical result management. Key elements of critical result reporting are discussed in view of the findings of various national surveys on existing laboratory practices, including data from our own survey in Australasia. Best practice recommendations are made that laboratories are expected to follow in order to provide high quality and safe service to patients. 相似文献
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ISABELLE LEFÈVRE KATARINA VOGEL‐MIKUŠ LUKA JEROMEL PRIMOŽ VAVPETIČ SÉBASTIEN PLANCHON IZTOK ARČON JOHANNES T VAN ELTEREN GILLES LEPOINT SYLVIE GOBERT JENNY RENAUT PRIMOŽ PELICON STANLEY LUTTS 《Plant, cell & environment》2014,37(6):1299-1320
Cadmium and zinc share many similar physiochemical properties, but their compartmentation, complexation and impact on other mineral element distribution in plant tissues may drastically differ. In this study, we address the impact of 10 μm Cd or 50 μm Zn treatments on ion distribution in leaves of a metallicolous population of the non‐hyperaccumulating species Zygophyllum fabago at tissue and cell level, and the consequences on the plant response through a combined physiological, proteomic and metabolite approach. Micro‐proton‐induced X‐ray emission and laser ablation inductively coupled mass spectrometry analyses indicated hot spots of Cd concentrations in the vicinity of vascular bundles in response to Cd treatment, essentially bound to S‐containing compounds as revealed by extended X‐ray absorption fine structure and non‐protein thiol compounds analyses. A preferential accumulation of Zn occurred in vascular bundle and spongy mesophyll in response to Zn treatment, and was mainly bound to O/N‐ligands. Leaf proteomics and physiological status evidenced a protection of photosynthetically active tissues and the maintenance of cell turgor through specific distribution and complexation of toxic ions, reallocation of some essential elements, synthesis of proteins involved in photosynthetic apparatus or C‐metabolism, and metabolite synthesis with some specificities regarding the considered heavy metal treatment. 相似文献
119.
Granular cell tumours (GCT) of the soft tissues are rare benign tumours but some time may be difficult to distinguish from malignant neoplasms. It is important that clinicians are aware of their existence. We present a new case of GCT of the soft tissues followed by a brief review of literature. 相似文献
120.
PeterMartin Bruch Holly AR Giles Carolin Kolb Sophie A Herbst Tina Becirovic Tobias Roider Junyan Lu Sebastian Scheinost Lena Wagner Jennifer Huellein Ivan Berest Mark Kriegsmann Katharina Kriegsmann Christiane Zgorzelski Peter Dreger Judith B Zaugg Carsten MüllerTidow Thorsten Zenz Wolfgang Huber Sascha Dietrich 《Molecular systems biology》2022,18(8)
The tumour microenvironment and genetic alterations collectively influence drug efficacy in cancer, but current evidence is limited and systematic analyses are lacking. Using chronic lymphocytic leukaemia (CLL) as a model disease, we investigated the influence of 17 microenvironmental stimuli on 12 drugs in 192 genetically characterised patient samples. Based on microenvironmental response, we identified four subgroups with distinct clinical outcomes beyond known prognostic markers. Response to multiple microenvironmental stimuli was amplified in trisomy 12 samples. Trisomy 12 was associated with a distinct epigenetic signature. Bromodomain inhibition reversed this epigenetic profile and could be used to target microenvironmental signalling in trisomy 12 CLL. We quantified the impact of microenvironmental stimuli on drug response and their dependence on genetic alterations, identifying interleukin 4 (IL4) and Toll‐like receptor (TLR) stimulation as the strongest actuators of drug resistance. IL4 and TLR signalling activity was increased in CLL‐infiltrated lymph nodes compared with healthy samples. High IL4 activity correlated with faster disease progression. The publicly available dataset can facilitate the investigation of cell‐extrinsic mechanisms of drug resistance and disease progression. 相似文献