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221.
Manjarivolo randrianirinai n. sp. is described from Southern Madagascar (Andohahela massif). Remarks on its ecology and morphology are added and a key to Manjarivolo species is provided as well as a complete photographic iconography of all known species. The scutellum of Aulonocnemini displays an unusual morphology, reported for the first time within Scarabaeoidea. For the first time we provide scanning electron microscope micrographs of the mouthparts of these beetles. 相似文献
222.
Maria R. Galdiero Cecilia Garlanda Sébastien Jaillon Gianni Marone Alberto Mantovani 《Journal of cellular physiology》2013,228(7):1404-1412
Tumor‐associated macrophages (TAMs) are a key component of the tumor microenvironment and orchestrate various aspects of cancer. Diversity and plasticity are hallmarks of cells of the monocyte–macrophage lineage. In response to distinct signals macrophages undergo M1 (classical) or M2 (alternative) activation, which represent extremes of a continuum in a spectrum of activation states. Metabolic adaptation is a key component of macrophage plasticity and polarization, instrumental to their function in homeostasis, immunity and inflammation. Generally, TAMs acquire an M2‐like phenotype that plays important roles in many aspects of tumor growth and progression. There is now evidence that also neutrophils can be driven towards distinct phenotypes in response to microenvironmental signals. The identification of mechanisms and molecules associated with macrophage and neutrophil plasticity and polarized activation provides a basis for new diagnostic and therapeutic strategies. J. Cell. Physiol. 228: 1404–1412, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
223.
Alberto Martire Rita Pepponi Maria Rosaria Domenici Antonella Ferrante Valentina Chiodi Patrizia Popoli 《Journal of neurochemistry》2013,125(2):225-235
NMDA receptor‐mediated excitotoxicity is thought to play a pivotal role in the pathogenesis of Huntington's disease (HD). The neurotrophin brain‐derived neurotrophic factor (BDNF), which is also highly involved in HD and whose effects are modulated by adenosine A2ARs, influences the activity and expression of striatal NMDA receptors. In electrophysiology experiments, we investigated the role of BDNF toward NMDA‐induced effects in HD models, and the possible involvement of A2ARs. In corticostriatal slices from wild‐type mice and age‐matched symptomatic R6/2 mice (a model of HD), NMDA application (75 μM) induced a transient or a permanent (i.e., toxic) reduction of field potential amplitude, respectively. BDNF (10 ng/mL) potentiated NMDA effects in wild‐type, while it protected from NMDA toxicity in R6/2 mice. Both effects of BDNF were prevented by A2AR blockade. The protective effect of BDNF against NMDA‐induced toxicity was reproduced in a cellular model of HD. These findings may have very important implications for the neuroprotective potential of BDNF and A2AR ligands in HD. 相似文献
224.
Paula Clemente Susana Peralta Alberto Cruz-Bermudez Lucía Echevarría Flavia Fontanesi Antoni Barrientos Miguel A. Fernandez-Moreno Rafael Garesse 《The Journal of biological chemistry》2013,288(12):8321-8331
Cytochrome c oxidase (COX) or complex IV of the mitochondrial respiratory chain plays a fundamental role in energy production of aerobic cells. In humans, COX deficiency is the most frequent cause of mitochondrial encephalomyopathies. Human COX is composed of 13 subunits of dual genetic origin, whose assembly requires an increasing number of nuclear-encoded accessory proteins known as assembly factors. Here, we have identified and characterized human CCDC56, an 11.7-kDa mitochondrial transmembrane protein, as a new factor essential for COX biogenesis. CCDC56 shares sequence similarity with the yeast COX assembly factor Coa3 and was termed hCOA3. hCOA3-silenced cells display a severe COX functional alteration owing to a decreased stability of newly synthesized COX1 and an impairment in the holoenzyme assembly process. We show that hCOA3 physically interacts with both the mitochondrial translation machinery and COX structural subunits. We conclude that hCOA3 stabilizes COX1 co-translationally and promotes its assembly with COX partner subunits. Finally, our results identify hCOA3 as a new candidate when screening for genes responsible for mitochondrial diseases associated with COX deficiency. 相似文献
225.
Alberto J. León David Banner Luoling Xu Longsi Ran Zhiyu Peng Kang Yi Chao Chen Fengping Xu Jinrong Huang Zhen Zhao Zhen Lin Stephen H. S. Huang Yuan Fang Alyson A. Kelvin Ted M. Ross Amber Farooqui David J. Kelvin 《Journal of virology》2013,87(4):1957-1966
Ferrets have become an indispensable tool in the understanding of influenza virus virulence and pathogenesis. Furthermore, ferrets are the preferred preclinical model for influenza vaccine and therapeutic testing. Here we characterized the influenza infectome during the different stages of the infectious process in ferrets with and without prior specific immunity to influenza. RNA from lung tissue and lymph nodes from infected and naïve animals was subjected to next-generation sequencing, followed by de novo data assembly and annotation of the resulting sequences; this process generated a library comprising 13,202 ferret mRNAs. Gene expression profiles during pandemic H1N1 (pdmH1N1) influenza virus infection were analyzed by digital gene expression and solid support microarrays. As expected during primary infection, innate immune responses were triggered in the lung tissue; meanwhile, in the lymphoid tissue, genes encoding antigen presentation and maturation of effector cells of adaptive immunity increased dramatically. After 5 days postinfection, the innate immune gene expression was replaced by the adaptive immune response, which correlates with viral clearance. Reinfection with homologous pandemic influenza virus resulted in a diminished innate immune response, early adaptive immune gene regulation, and a reduction in clinical severity. The fully annotated ferret infectome will be a critical aid to the understanding of the molecular events that regulate disease severity and host-influenza virus interactions among seasonal, pandemic, and highly pathogenic avian influenzas. 相似文献
226.
Alberto Szekely 《Ocean Development & International Law》2013,44(2):195-211
Abstract The purpose of this work is twofold. First, to analyze the general significance, from an international point of view, of the unilateral establishment by Mexico of its 200‐mile Exclusive Economic Zone as from June 6, 1976, in order to conclude on both its legality and its opportunity, within the framework of, respectively, the present standing of the emerging rules of the new law of the sea and the stage at which the Third United Nations Conference on the Law of the Sea finds itself after four sessions of negotiations. The arguments resorted to by Mexico in order to defend the legality and opportunity of its claim are analyzed in detail. Secondly, a study is made on whether or. not the unilateral claim of establishment of the Exclusive Economic Zone is contrary to Mexico's traditional law of the sea practice, this practice consisting of a permanent policy by Mexico, throughout its independent life, of waiting for international agreements to be concluded, or for international customs to be definitely shaped, before proceeding to the unilateral delimitation of its marine zones. 相似文献
227.
Yasmin Rubio-Palis Mariapia Bevilacqua Domingo Alberto Medina Jorge Ernesto Moreno Lya Cárdenas Víctor Sánchez Yarys Estrada William Anaya ángela Martínez 《Memórias do Instituto Oswaldo Cruz》2013,108(2):220-228
To explore the effects of deforestation and resulting differences in vegetation and land cover on entomological parameters, such as anopheline species composition, abundance, biting rate, parity and entomological inoculation rate (EIR), three villages were selected in the Lower Caura River Basin, state of Bolívar, Venezuela. All-night mosquito collections were conducted between March 2008-January 2009 using CDC light traps and Mosquito Magnet(r) Liberty Plus. Human landing catches were performed between 06:00 pm-10:00 pm, when anophelines were most active. Four types of vegetation were identified. The Annual Parasite Index was not correlated with the type of vegetation. The least abundantly forested village had the highest anopheline abundance, biting rate and species diversity. Anopheles darlingi and Anopheles nuneztovari were the most abundant species and were collected in all three villages. Both species showed unique biting cycles. The more abundantly forested village of El Palmar reported the highest EIR. The results confirmed previous observations that the impacts of deforestation and resulting changes in vegetation cover on malaria transmission are complex and vary locally. 相似文献
228.
Dominic Frigon Basanta Kumar Biswal Alberto Mazza Luke Masson Ronald Gehr 《Applied and environmental microbiology》2013,79(3):835-844
Effluents discharged from wastewater treatment plants are possible sources of pathogenic bacteria, including Escherichia coli, in the freshwater environment, and determining the possible selection of pathogens is important. This study evaluated the impact of activated sludge and physicochemical wastewater treatment processes on the prevalence of potentially virulent E. coli. A total of 719 E. coli isolates collected from four municipal plants in Québec before and after treatment were characterized by using a customized DNA microarray to determine the impact of treatment processes on the frequency of specific pathotypes and virulence genes. The percentages of potentially pathogenic E. coli isolates in the plant influents varied between 26 and 51%, and in the effluents, the percentages were 14 to 31%, for a reduction observed at all plants ranging between 14 and 45%. Pathotypes associated with extraintestinal pathogenic E. coli (ExPEC) were the most abundant at three of the four plants and represented 24% of all isolates, while intestinal pathogenic E. coli pathotypes (IPEC) represented 10% of the isolates. At the plant where ExPEC isolates were not the most abundant, a large number of isolates were classified as both ExPEC and IPEC; overall, 6% of the isolates were classified in both groups, with the majority being from the same plant. The reduction of the proportion of pathogenic E. coli could not be explained by the preferential loss of one virulence gene or one type of virulence factor; however, the quinolone resistance gene (qnrS) appears to enhance the loss of virulence genes, suggesting a mechanism involving the loss of pathogenicity islands. 相似文献
229.
Sabrina Duranti Francesca Turroni Christian Milani Elena Foroni Francesca Bottacini Fabio Dal Bello Alberto Ferrarini Massimo Delledonne Douwe van Sinderen Marco Ventura 《Applied and environmental microbiology》2013,79(1):336-346
In the current work, we describe genome diversity and core genome sequences among representatives of three bifidobacterial species, i.e., Bifidobacterium adolescentis, Bifidobacterium catenulatum, and Bifidobacterium pseudocatenulatum, by employing a polyphasic approach involving analysis of 16S rRNA gene and 16S-23S internal transcribed spacer (ITS) sequences, pulsed-field gel electrophoresis (PFGE), and comparative genomic hybridization (CGH) assays. 相似文献
230.
Nicola Luchi Luisa Ghelardini Lassaad Belbahri Marion Quartier Alberto Santini 《Applied and environmental microbiology》2013,79(17):5394-5404
Ceratocystis platani is the causal agent of canker stain of plane trees, a lethal disease able to kill mature trees in one or two successive growing seasons. The pathogen is a quarantine organism and has a negative impact on anthropogenic and natural populations of plane trees. Contaminated sawdust produced during pruning and sanitation fellings can contribute to disease spread. The goal of this study was to design a rapid, real-time quantitative PCR assay to detect a C. platani airborne inoculum. Airborne inoculum traps (AITs) were placed in an urban setting in the city of Florence, Italy, where the disease was present. Primers and TaqMan minor groove binder (MGB) probes were designed to target cerato-platanin (CP) and internal transcribed spacer 2 (ITS2) genes. The detection limits of the assay were 0.05 pg/μl and 2 fg/μl of fungal DNA for CP and ITS, respectively. Pathogen detection directly from AITs demonstrated specificity and high sensitivity for C. platani, detecting DNA concentrations as low as 1.2 × 10−2 to 1.4 × 10−2 pg/μl, corresponding to ∼10 conidia per ml. Airborne inoculum traps were able to detect the C. platani inoculum within 200 m of the closest symptomatic infected plane tree. The combination of airborne trapping and real-time quantitative PCR assay provides a rapid and sensitive method for the specific detection of a C. platani inoculum. This technique may be used to identify the period of highest risk of pathogen spread in a site, thus helping disease management. 相似文献