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In the marine environment associations between picoplankton and copepods are very important not only for the lifestyle of these animals, but also for marine ecosystems and human health. In the present study we investigated the biofouling of Tigriopus fulvus in culture and possible effects of this colonization by means of scanning electron microscopy and epifluorescence microscopy. These investigations show that T. fulvus is heavily and not uniformly colonized by bacteria and algae.  相似文献   
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Glycosaminoglycans extracted by CPC precipitation from chick embryo skin at 9, 12, 15, 18, 21 days of incubation were separated by three different electrophoretic methods on acetate cellulose strips. We observed the presence of Hyaluronic acid, Dermatan Sulfate and Chondroitin-4-Sulfate during the whole period considered and of Heparan Sulfate only after the 9th day. Dermatan Sulfate increases until the 15th day then decreases progressively; on the contrary Hyaluronic acid and Chondroitin-4-Sulfate decrease during days 9 to 15 then increase until hatching. Heparan Sulfate appear the 9th day then increases progressively until hatching.  相似文献   
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OBJECTIVE: To evaluate the thyroidal lymphoid infiltrate (TLI) in thyroidal functional status (TFS) for differences among patients with Hashimoto's thyroiditis (HT). STUDY DESIGN: Flow-cytometry (FC) was applied to thyroidal fine-needle cytology samples in 57 patients. TLI was analyzed using a fluorescence-activated cell sorter (FACS) scan and fluorescence antibodies CD3, CD4, CD5, CD8, CD10, and CD19 and kappa and lambda light chains. TFS was determined by serum thyroid-stimulating hormone (TSH), FT3 and FT4 immunoassays, in specific clinical settings, to classify the cases as hyperthyroid, euthyroid and hypothyroid. FC assessment was then compared with the corresponding TFS. RESULTS: B-lymphocytes were present in 44 cases (77%). T-lymphocytes were present in all the cases; CD4/CD8 = 2:1 ratio was observed in 16 euthyroid, 1 hyperthyroid and 3 hypothyroid; CD4/CD8 > or = 3:1 ratio in 22 euthyroid, 2 hyperthyroid and 2 hypothyroid cases; CD4/CD8 < or = 1:1 ratio in 1 euthyroid, 3 hyperthyroid and in 7 hypothyroid cases. Grouping hyperthyroid and hypothyroid cases, a significant association was observed with the CD4/CD8 < or = 1:1 ratio (p < 0.01). CONCLUSION: Intrathyroidal CD4/CD8 < 1:1 ratio might be the expression of intense apoptosis in the early phases of HT, generally followed by the restoration of CD4/CD8 balance; persistence of increased intrathyroidal CD8 might be related to intense thyroidal damage and thus an increasing risk of hypothyroidism.  相似文献   
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Triatomine assassin bugs comprise hematophagous insect vectors of Trypanosoma cruzi, the causative agent of Chagas disease. Although the microbiome of these species has been investigated to some extent, only one virus infecting Triatoma infestans has been identified to date. Here, we describe for the first time seven (+) single-strand RNA viruses (RpV1-7) infecting Rhodnius prolixus, a primary vector of Chagas disease in Central and South America. We show that the RpVs belong to the Iflaviridae, Permutotetraviridae and Solemoviridae and are vertically transmitted from the mothers to the progeny via transovarial transmission. Consistent with this, all the RpVs, except RpV2 that is related to the entomopathogenic Slow bee paralysis virus, established persistent infections in our R. prolixus colony. Furthermore, we show that R. prolixus ovaries express 22-nucleotide viral siRNAs (vsiRNAs), but not viral piRNAs, that originate from the processing of dsRNA intermediates during viral replication of the RpVs. Interestingly, the permutotetraviruses and sobemoviruses display shared pools of vsiRNAs that might provide the basis for a cross-immunity system. The vsiRNAs are maternally deposited in the eggs, where they likely contribute to reduce the viral load and protect the developing embryos. Our results unveil for the first time a complex core virome in R. prolixus and begin to shed light on the RNAi-based antiviral defenses in triatomines.  相似文献   
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P. Zeppa, E. Vigliar, I. Cozzolino, G. Troncone, M. Picardi, A. De Renzo, F. Grimaldi, F. Pane, A. Vetrani and L. Palombini
Fine needle aspiration cytology and flow cytometry immunophenotyping of non‐Hodgkin lymphoma: can we do better? Objective: To evaluate the diagnostic efficiency of fine needle aspiration cytology/flow cytometry (FNAC/FC) in the diagnosis and classification of non‐Hodgkin lymphoma (NHL) in a series of 446 cases and to compare the results with those of previous experiences to evaluate whether there had been an improvement in FNAC/FC diagnostic accuracy. Methods: FNAC/FC was used to analyse 446 cases of benign reactive hyperplasia (BRH), NHL and NHL relapse (rNHL) in 362 lymph nodes and 84 extranodal lesions. When a diagnosis of NHL was reached, a classification was attempted combining FC data and cytological features. Sensitivity, specificity and positive and negative predictive values (PPV and NPV) of FNAC/FC in the diagnosis and classification of NHL were calculated and compared with those available in the literature. Results: FNAC/FC provided a diagnosis of NHL and rNHL in 245 cases and of BRH in 188 cases. In nine cases, the diagnosis was ‘suggestive of NHL’ (sNHL) and in four cases was inadequate. Histology and clinical follow‐up confirmed 102 cases of NHL and detected one false positive. In 18 cases of BRH diagnosed by FNAC/FC, histological examination revealed 14 BRH and four NHL (false negatives). All nine cases diagnosed as sNHL were confirmed by histology. Including sNHL cases as false negatives, statistical analysis showed 94.9% sensitivity, 99.4% specificity, 99.6% PPV and 93.4% NPV in the diagnosis of NHL. A specific subtype was diagnosed in 125 cases and confirmed in 67 of 70 cases that had histological biopsies. Statistical analysis did not demonstrate significant improvements between the present series and previous studies either in diagnosis or in classification of NHL. Conclusions: FNAC/FC is a fundamental tool in the diagnosis and classification of NHL but the exiguity of diagnostic material and other technical and clinical limitations will probably continue to limit further improvement of the technique.  相似文献   
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Imatinib mesylate is a potent inhibitor of Bcr-Abl tyrosine kinase, an oncoprotein that plays a key role in the development of chronic myeloid leukemia. Consequently, imatinib is used as front-line therapy for this disease. A major concern in imatinib treatment is the emergence of resistance to the drug. Here we used the imatinib-resistant KCL22R and imatinib-sensitive KCL22S cells in which none of the known resistance mechanisms has been detected and hence novel Bcr-Abl activity-independent mechanisms could be envisaged. We characterized proteins that were differentially expressed between the KCL22R and KCL22S cells. Using two-dimensional differential gel electrophoresis coupled with mass spectrometry and Western blot analysis we identified 51 differentially expressed proteins: 27 were over-expressed and 24 were under-expressed in KCL22R versus KCL22S cells. Several of these proteins are likely to be involved in such survival mechanisms as modulation of redox balance and activation of anti-apoptotic pathways mediated by NF-κB and Ras-MAPK signaling. The data reported may be useful for further studies on mechanisms of imatinib resistance and for the screening of biomarkers to develop new combinatorial therapeutic approaches.  相似文献   
19.
Saccone G  Pane A  Polito LC 《Genetica》2002,116(1):15-23
Sex determination mechanisms, differing in their modality, are widely represented in all the various animal taxa, even at the intraspecific level. Within the highly diversified Class Insecta, Drosophila has been used to unravel the mechanistic molecular and genetic interactions that are involved in sex determination. Indeed, the molecularly characterized genes of the Drosophila sex determination hierarchy X:A> Sxl> tra> dsxhave been fruitful starting points in the cloning of homologous genes from other insect species. This cascade seems to control sex determination in all Drosophila species. However, no sex-specific regulatory Sxlhomologues have been isolated from the Mediterranean fruitfly (medfly), Ceratitis capitata, the housefly, Musca domestica, Chrysomya rufifaciesnor from the distantly related phorid fly Megaselia scalaris. Moreover, all these other species use primary signals different from the intricate X:A counting system of Drosophila. However, dsxhomologues isolated from these and other dipteran species as well as from the silkmoth, Bombyx mori, share a conserved sex-specific regulation based on alternative splicing. An understanding of the sex determination mechanisms in insects that are of agricultural or public health importance may help in the development of improved methods for their control using the sterile insect technique.  相似文献   
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In aquatic environments heterotrophic flagellates are an important component within the microbial loop and the food web, owing to their involvement in the energy transfer and flux and as an intermediate link between bacteria and primary producers, and greater organisms, such as other protists and metazoan consumers. In the microbial loop heterotrophic flagellates highly contribute to fast biomass and nutrient recycling and to the production in aquatic environments. In fact, these protists consume efficiently viruses, bacteria, cyanobacteria and picophytoplankton, and are grazed mainly by other protists, rotifers and small crustaceans. In this paper the knowledge about these unicellular organisms is reviewed, taking into particular account their ecological relationships and trophic role within the plankton community of marine and freshwater environments.  相似文献   
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