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991.
Antnio Ralph Medeiros-Sousa Gabriel Zorello Laporta Renato Mendes Coutinho Luis Filipe Mucci Mauro Toledo Marrelli 《PLoS neglected tropical diseases》2021,15(2)
Transmission foci of autochthonous malaria caused by Plasmodium vivax-like parasites have frequently been reported in the Atlantic Forest in Southeastern and Southern Brazil. Evidence suggests that malaria is a zoonosis in these areas as human infections by simian Plasmodium species have been detected, and the main vector of malaria in the Atlantic Forest, Anopheles (Kerteszia) cruzii, can blood feed on human and simian hosts. In view of the lack of models that seek to predict the dynamics of zoonotic transmission in this part of the Atlantic Forest, the present study proposes a new deterministic mathematical model that includes a transmission compartment for non-human primates and parameters that take into account vector displacement between the upper and lower forest strata. The effects of variations in the abundance and acrodendrophily of An. cruzii on the prevalence of infected humans in the study area and the basic reproduction number (R0) for malaria were analyzed. The model parameters are based on the literature and fitting of the empirical data. Simulations performed with the model indicate that (1) an increase in the abundance of the vector in relation to the total number of blood-seeking mosquitoes leads to an asymptotic increase in both the proportion of infected individuals at steady state and R0; (2) the proportion of infected humans at steady state is higher when displacement of the vector mosquito between the forest strata increases; and (3) in most scenarios, Plasmodium transmission cannot be sustained only between mosquitoes and humans, which implies that non-human primates play an important role in maintaining the transmission cycle. The proposed model contributes to a better understanding of the dynamics of malaria transmission in the Atlantic Forest. 相似文献
992.
Whole-genome characterization of lung adenocarcinomas lacking alterations in the RTK/RAS/RAF pathway
Jian Carrot-Zhang Xiaotong Yao Siddhartha Devarakonda Aditya Deshpande Jeffrey S. Damrauer Tiago Chedraoui Silva Christopher K. Wong Hyo Young Choi Ina Felau A. Gordon Robertson Mauro A.A. Castro Lisui Bao Esther Rheinbay Eric Minwei Liu Tuan Trieu David Haan Christina Yau Toshinori Hinoue Marcin Imielinski 《Cell reports》2021,34(8):108784
993.
Antinori A Marcotullio S Ammassari A Andreoni M Angarano G Carosi G Cinque P d'Arminio Monforte A Di Perri G Ensoli B Ferrazzi E Galli M Mastroianni C Matteelli A Mazzotta F Moroni M Palù G Puoti M Puro V Rizzardini G Sagnelli E Suter F Vella S Lazzarin A;Italian HIV Guidelines Working Group 《The new microbiologica》2011,34(2):109-146
994.
995.
Rosa M Giannicola G Servello D Marceglia S Pacchetti C Porta M Sassi M Scelzo E Barbieri S Priori A 《Neuro-Signals》2011,19(3):151-162
In the past years, local field potential (LFP) signals recorded from the subthalamic nucleus (STN) in patients undergoing deep brain stimulation (DBS) for Parkinson's disease (PD) disclosed that DBS has a controversial effect on STN beta oscillations recorded 2-7 days after surgery for macroelectrode implantation. Nothing is known about these DBS-induced oscillatory changes 30 days after surgery. We recorded STN LFPs during ongoing DBS in 7 patients with PD, immediately (hyperacute phase) and 30 days (chronic phase) after surgery. STN LFP recordings showed stationary intranuclear STN beta LFP activity in hyperacute and chronic phases, confirming that beta peaks were also present in chronic recordings. Power spectra of nuclei with significant beta activity (54% of the sample) showed that it decreased significantly during DBS (p=0.021) under both recording conditions. The time course of beta activity showed more evident DBS-induced changes in the chronic than in the hyperacute phase (p=0.014). DBS-induced changes in STN beta LFPs in patients undergoing DBS in chronic phase provide useful information for developing a new neurosignal-controlled adaptive DBS system. 相似文献
996.
997.
Mutualistic interactions involving pollination and ant-plant mutualistic networks typically feature tightly linked species grouped in modules. However, such modularity is infrequent in seed dispersal networks, presumably because research on those networks predominantly includes a single taxonomic animal group (e.g. birds). Herein, for the first time, we examine the pattern of interaction in a network that includes multiple taxonomic groups of seed dispersers, and the mechanisms underlying modularity. We found that the network was nested and modular, with five distinguishable modules. Our examination of the mechanisms underlying such modularity showed that plant and animal trait values were associated with specific modules but phylogenetic effect was limited. Thus, the pattern of interaction in this network is only partially explained by shared evolutionary history. We conclude that the observed modularity emerged by a combination of phylogenetic history and trait convergence of phylogenetically unrelated species, shaped by interactions with particular types of dispersal agents. 相似文献
998.
Ricci I Damiani C Scuppa P Mosca M Crotti E Rossi P Rizzi A Capone A Gonella E Ballarini P Chouaia B Sagnon N Esposito F Alma A Mandrioli M Sacchi L Bandi C Daffonchio D Favia G 《Environmental microbiology》2011,13(4):911-921
While symbiosis between bacteria and insects has been thoroughly investigated in the last two decades, investments on the study of yeasts associated with insects have been limited. Insect-associated yeasts are placed on different branches of the phylogenetic tree of fungi, indicating that these associations evolved independently on several occasions. Isolation of yeasts is frequently reported from insect habitats, and in some cases yeasts have been detected in the insect gut and in other organs/tissues. Here we show that the yeast Wickerhamomyces anomalus, previously known as Pichia anomala, is stably associated with the mosquito Anopheles stephensi, a main vector of malaria in Asia. Wickerhamomyces anomalus colonized pre-adult stages (larvae L(1)-L(4) and pupae) and adults of different sex and age and could be isolated in pure culture. By a combination of transmission electron microscopy and fluorescent in situ hybridization techniques, W. anomalus was shown to localize in the midgut and in both the male and female reproductive systems, suggesting multiple transmission patterns. 相似文献
999.
Raddadi N Gonella E Camerota C Pizzinat A Tedeschi R Crotti E Mandrioli M Bianco PA Daffonchio D Alma A 《Environmental microbiology》2011,13(2):414-426
'Candidatus Liberibacter spp.' cause serious plant diseases. 'Candidatus Liberibacter asiaticus', 'Ca. L. americanus' and 'Ca. L. africanus' are the aetiological agents of citrus greening (Huanglongbing) in Asia, America and Africa. 'Candidatus Liberibacter solanacearum' causes diseases in Solanaceae in America and New Zealand. All four species are vectored by psyllid insects of different genera. Here, we show that the pear psyllid pest Cacopsylla pyri (L.) hosts a novel liberibacter species that we named 'Ca. Liberibacter europaeus'. It can bloom to high titres in the psyllid host, with more than 10(9) 16S rRNA gene copies per individual. Fluorescent in situ hybridization experiments showed that 'Ca. L. europaeus' is present in the host midgut lumen, salivary glands and Malpighian tubules. 'Candidatus L. europaeus' has a relatively high prevalence (> 51%) in C. pyri from different areas in the Piedmont and Valle d'Aosta regions in Italy and can be transmitted to pear plants in experimental transmission trials. However, even though high titres of the bacterium (more than 10(8) 16S rRNA gene copies g(-1) of pear plant tissue) could be detected, in the pear tissues no specific disease symptoms could be observed in the infected plants over a 6-month period. Despite liberibacters representing potential quarantine organisms, 'Ca. L. europaeus', first described in Italy and Europe, apparently behaves as an endophyte rather than a pathogen. 相似文献
1000.
Christina Orsmark Pietras Johanna Vendelin Francesca Anedda Sara Bruce Mikael Adner Lilli Sundman Ville Pulkkinen Harri Alenius Mauro D'Amato Cilla Söderhäll Juha Kere 《BMC pulmonary medicine》2011,11(1):39