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91.
Christine Demanche Manjula Deville Johan Michaux Véronique Barriel Claire Pin?on Cécile Marie Aliouat-Denis Muriel Pottier Christophe No?l Eric Viscogliosi El Moukhtar Aliouat Eduardo Dei-Cas Serge Morand Jacques Guillot 《PloS one》2015,10(4)
Pneumocystis fungi represent a highly diversified biological group with numerous species, which display a strong host-specificity suggesting a long co-speciation process. In the present study, the presence and genetic diversity of Pneumocystis organisms was investigated in 203 lung samples from woodmice (Apodemus sylvaticus) collected on western continental Europe and Mediterranean islands. The presence of Pneumocystis DNA was assessed by nested PCR at both large and small mitochondrial subunit (mtLSU and mtSSU) rRNA loci. Direct sequencing of nested PCR products demonstrated a very high variability among woodmouse-derived Pneumocystis organisms with a total number of 30 distinct combined mtLSU and mtSSU sequence types. However, the genetic divergence among these sequence types was very low (up to 3.87%) and the presence of several Pneumocystis species within Apodemus sylvaticus was considered unlikely. The analysis of the genetic structure of woodmouse-derived Pneumocystis revealed two distinct groups. The first one comprised Pneumocystis from woodmice collected in continental Spain, France and Balearic islands. The second one included Pneumocystis from woodmice collected in continental Italy, Corsica and Sicily. These two genetic groups were in accordance with the two lineages currently described within the host species Apodemus sylvaticus. Pneumocystis organisms are emerging as powerful tools for phylogeographic studies in mammals. 相似文献
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C. Engohan‐Aloghe N. Hottat J. Cosaert R. Boutemy I. Fayt J.‐C. Noël 《Cytopathology》2010,21(3):161-163
C. Engohan‐Aloghe, N. Hottat, J. Cosaert, R. Boutemy, I. Fayt and J.‐C. Noël Evaluation of accuracy of fine needle aspiration cytology in BI‐RADS3 category breast lesions: cytohistological correlation in 337 cases Objective: To evaluate the accuracy of fine needle aspiration cytology (FNAC) in BI‐RADS3 breast lesions. Methods: Between January 2004 and December 2007, 337 cases from BI‐RADS3 lesions underwent FNAC. Three to six needle passes were made on each patient. In 67 cases (20%) a histological biopsy was performed. Cytological and histological interpretations were performed by the same pathologist. Results: The histological diagnosis showed that 88% (59/67) of BI‐RADS3 breast lesions were benign. Only 6% (4/67) were malignant, consisting of ductal carcinoma in situ and infiltrating ductal carcinoma. Conclusion: BI‐RADS3 lesions remain disruptive in their management. However, the correlation between cytology and histology showed that most of these lesions were benign and that finally FNAC remains a useful and accurate test in the management of these lesions. 相似文献
95.
Jehun Choi Sung Jin Bae Young Mi Ha Jae Kyung No Eun Kyeong Lee Jun Sik Lee Suhee Song Hyojin Lee Hongsuk Suh Byung Pal Yu Hae Young Chung 《Bioorganic & medicinal chemistry letters》2010,20(16):4882-4884
In searching for new agents with a depigmenting effect, we synthesized a derivative of resveratrol, 5-(6-hydroxy-2-naphthyl)-1,2,3-benzenetriol (5HNB) with a potent tyrosinase inhibitory activity. 5HNB inhibited mushroom tyrosinase with an IC50 value of 2.95 μM, which is more potent than the well-known anti-tyrosinase activity of kojic acid (IC50 = 38.24). The results of the enzymatic inhibition kinetics by Lineweaver–Burk analysis indicated 5HNB inhibits tyrosinase non-competitively when l-tyrosine was used as the substrate. Based on the strong inhibitory action of 5HNB, it is expected that 5HNB can suppress melanin production in which tyrosinase plays the essential role. Our expectation was confirmed by the experimentations with B16 melanoma cells in which 5HNB inhibited melanin production. We propose that 5HNB might have skin-whitening effects as well as therapeutic potential for treating skin pigmentation disorders. 相似文献
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Marie Noël K. Djuikouo Jean‐Louis Doucet Charlemagne K. Nguembou Simon L. Lewis Bonaventure Sonké 《African Journal of Ecology》2010,48(4):1053-1063
We present tree community diversity, species composition, basal area and aboveground biomass of three forest types in the Dja Biosphere Reserve, in South‐East Cameroon, part of the contiguous tropical forest of the Congo Basin. A total of fourteen, 1 ha, plots were established in heterogeneous terra firme forests (TFF), Gilbertiodendron dewevrei forests (GDF) and periodically flooded forests (PFF). A total of 281 tree species with diameter ≥10 cm were recorded. The Shannon diversity index was significantly higher in TFF (5.7 ± 0.28) and PFF (5.6 ± 0.23) than in GDF (2.29 ± 0.48) (ANOVA, F2,11 = 139.75, P < 0.001). While tree density did not differ between forest types (F2,11 = 3.50, P = 0.06), basal area differed significantly (F2,11 = 7.38, P = 0.009), as did aboveground biomass (F2,11 = 17.95, P < 0.001). Mean AGB values were respectively, 596.1 ± 62.24, 401.67 ± 58.06 and 383.14 ± 61.91 Mg ha?1 in GDF, TFF and PFF. Variation in the abundance of trees with large diameter was the main reason for these differences. Few dominant species made the greatest contribution to the AGB. G. dewevrei, accounted for 83% of AGB in GDF, Penthaclethra macrophylla for 9.9% in TFF and Uapaca heudolotii for 10.6% in PFF. The importance of preserving G. dewevrei forest in the context of ‘Reducing Emissions from Deforestation and forest Degradation’ (REDD) policies is discussed. 相似文献
98.
Antoine Nougairède Laetitia Ninove Christine Zandotti Nicolas Salez Karine Mantey Noémie Resseguier Céline Gazin Didier Raoult Rémi N. Charrel Xavier de Lamballerie 《PloS one》2010,5(2)
Background
In April 2009, the first cases of pandemic (H1N1)-2009 influenza [H1N1sw] virus were detected in France. Virological surveillance was undertaken in reference laboratories of the seven French Defence Zones.Methodology/Principal Findings
We report results of virological analyses performed in the Public Hospitals of Marseille during the first months of the outbreak. (i) Nasal swabs were tested using rapid influenza diagnostic test (RIDT) and two RT-PCR assays. Epidemiological characteristics of the 99 first suspected cases were analyzed, including detection of influenza virus and 18 other respiratory viruses. During three months, a total of 1,815 patients were tested (including 236 patients infected H1N1sw virus) and distribution in age groups and results of RIDT were analyzed. (ii) 600 sera received before April 2009 and randomly selected from in-patients were tested by a standard hemagglutination inhibition assay for antibody to the novel H1N1sw virus. (iii) One early (May 2009) and one late (July 2009) viral isolates were characterized by sequencing the complete hemagglutinine and neuraminidase genes. (iiii) Epidemiological characteristics of a cluster of cases that occurred in July 2009 in a summer camp were analyzed.Conclusions/Significance
This study presents new virological and epidemiological data regarding infection by the pandemic A/H1N1 virus in Europe. Distribution in age groups was found to be similar to that previously reported for seasonal H1N1. The first seroprevalence data made available for a European population suggest a previous exposure of individuals over 40 years old to influenza viruses antigenically related to the pandemic (H1N1)-2009 virus. Genomic analysis indicates that strains harbouring a new amino-acid pattern in the neuraminidase gene appeared secondarily and tended to supplant the first strains. Finally, in contrast with previous reports, our data support the use of RIDT for the detection of infection in children, especially in the context of the investigation of grouped cases. 相似文献99.
100.
Newly identified biologically active and proteolysis-resistant VEGF-A isoform VEGF111 is induced by genotoxic agents
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Mineur P Colige AC Deroanne CF Dubail J Kesteloot F Habraken Y Noël A Vöö S Waltenberger J Lapière CM Nusgens BV Lambert CA 《The Journal of cell biology》2007,179(6):1261-1273
Ultraviolet B and genotoxic drugs induce the expression of a vascular endothelial growth factor A (VEGF-A) splice variant (VEGF111) encoded by exons 1–4 and 8 in many cultured cells. Although not detected in a series of normal human and mouse tissue, VEGF111 expression is induced in MCF-7 xenografts in nude mice upon treatment by camptothecin. The skipping of exons that contain proteolytic cleavage sites and extracellular matrix–binding domains makes VEGF111 diffusible and resistant to proteolysis. Recombinant VEGF111 activates VEGF receptor 2 (VEGF-R2) and extracellularly regulated kinase 1/2 in human umbilical vascular endothelial cells and porcine aortic endothelial cells expressing VEGF-R2. The mitogenic and chemotactic activity and VEGF111's ability to promote vascular network formation during embyonic stem cell differentiation are similar to those of VEGF121 and 165. Tumors in nude mice formed by HEK293 cells expressing VEGF111 develop a more widespread network of numerous small vessels in the peritumoral tissue than those expressing other isoforms. Its potent angiogenic activity and remarkable resistance to proteolysis makes VEGF111 a potential adverse factor during chemotherapy but a beneficial therapeutic tool for ischemic diseases. 相似文献